The ZLUG Thread

[Hogtamer]

OK, we've talked about it and after weighing the pros and cons I'm going to try to produce a full bore ZINC slug load for a 3" rifled 12 guage. I just ordered this mold from Accurate Molds.
http://www.accuratemolds.com/bullet_detail.php?bullet=73-860B-D.png

From what I can read the Zamak 3 alloy looks like the best choice, so this will be coming soon.
http://www.rotometals.com/product-p/zamak-3-ingots.htm

If I can cast these it should yield a slug that weighs 1.31 oz. There's a 3 week turnaround on the mold. In the mean time I will aqcuire a new clean pot and ladle to insure no contamination. Until I actually begin casting trials, comments are welcome, especially about load recommendations and wad column composition. My powder choices are Steel, Longshot and 800-X. Wish me luck and let's have at it!

[OBCoal]

Good luck and hope it works out for you. Nice looking slug mold.

[longbow]

I guess my only comment is that the bearing bands look pretty beefy for a slug as hard as zinc. It might take some pressure to engrave that boolit.

Not sure how one would check that other than to use a barrel push through to determine just how much force is required to engrave then use that to determine pressure.

I don't think it would phase me in a center fire rifle but I have visions of a snake swallowing a gopher when I think of a hard slug being pushed through a thin walled shotgun barrel... or are you using an bull barrel?

Regardless, I would use the slowest shotgun powder you have to minimize pressure spike.

If the slug shrinks more than lead then engraving may be fairly shallow so mitigating the hardness issue some. Hard to say without testing. Maybe someone has already tried and can advise.

I think I would be inclined to use felt or fiber wad under the slug to raise it up to crimp height and for a bit of cushion effect, and a good plastic gas seal over the powder.

Just my thoughts.

Longbow

[cpileri]

I'm interested.

[Red River Rick]

Cutting the Sprue on a zinc bullet may prove a bit troublesome.

RRR

[Hogtamer]

Thinking may have to enlarge sprue hole a bit and quick pore with ladel at ~ 800*. Would the Zamak 3 (about 4% aluminum) be a better choice tha pure zinc? If I understand the bit of aluminum would help fillout. Any shared experience would be welcome.
LB, the fit to bore is a bit of a **** shoot until I actually get the mold and cast some I think. The snake swallowing the gopher is a disturbing image something I plan on avoiding. Depending on actual size of mold (+ or - 002) and amount of shrinkage I really don't know what to expect. What would be acceptable amount of pressure to get slug down bore if it is oversize considering hardness of alloy?

[bikerbeans]

HT,

I hope ur mold works with zinc, because a 2 oz lead 12ga slug will be a handful at normal slug velocity. Good luck and keep us posted.

BB

[longbow]

Yeah, Red River Rick brings up a good point too about cutting the sprue. That may well be troublesome. I would not go enlarging the sprue hole at least until you do some casting.

I will say that one of the ZAMAK alloys is probably better than pure zinc... that or a die casting alloy. Die casting is done under pressure but the zinc also has to flow well so a die casting alloy might be the best overall.

You may also have to pre-heat that mould quite a bit before casting. Another reason to go with iron.

Sizing will also be an issue if the slug is big. Not sure how you handle that. Seems to me turbo had some comments about that in a post. I would figure a knurled or tumble lube grooved slug might allow zinc to be sized easier than with beefy (like skookum) driving bands. Now a hammer sizing die might just work okay. Turn the correct sizing die diameter, make a close fitting punch and use an "appropriate" sized persuader (hammer) to drive the slug through. Likely much easier than trying in a press. Hmmm... unless you have an arbor press that is.

You may well not need or want a full groove diameter slug and a plastic gas seal behind will take care of gas so no need anyway. I think engraving effort will be what you want to optimize and with zinc as hard as it is you may not need a lot of engraving depth.

All speculation on my part though.

I do work for a lead/zinc smelter so I will see if I can get any info on best zinc alloy for casting. Not sure I will get anything as the plant just mixes alloys to suit clients orders and we do not do any casting except slabs and jumbos... no small parts.

This will be interesting. I am glad you have taken the jump and are giving it a try.

Longbow

[bikerbeans]

LB,

If it would take a hammer to "push" a zinc slug through a size die, what would it take to remove a zinc squib from halfway down the bore?

BB

[longbow]

Well, good question. I have to think that once engraved if wouldn't be too bad. I think the initial engraving might be the issue. But again, speculation on my part.

Longbow

[Hogtamer]

Disappointment....Got an email and a refund from Tom at Accurate mold. He's very thorough and when I told him to use a 5% thermal shrinkage rate from zinc alloy he calculated that to get a .729 slug the mold would have to be .766, too big for the blocks he uses. While that speaks well for his attention to detail it leaves me with no alternative that I have come up with yet. The 5% number is a bit arbitrary as metallurigcal sites I visited gave shrinkage rates from 3.5% to 6.5%, so I used a mid-range and hoped to get lucky. What I am considering now is casting some minies from a lyman mold I have that casts oversize in lead, using the Zamak 3 alloy and trying to determine an actual shrinkage rate to work with. From that I can perhaps come up with a more precise guesstimate that would allow me to buy a slug mold that would cast .600 in zinc to fit some steel shot wads I have to create a sabot slug. Nothing seems easy! Anyone with a better idea? Seems that a member here who has actual experience with zinc (turbo 1889) pulled his threads and no longer participates in the forum. Does anyone have email contact info for him that he might communicate privately? Failing that, any suggestions about where to go with this?

[cpileri]

Looks like you are stuck w a wad-slug combo; which does eliminate some of the problems that have been brought up; i'd say.

Still interested!

C-

[Red River Rick]

I've machined hundreds of moulds over the past 25 years for a customer of mine that does zinc injection moulding. I've used 0.06% (0.006" per inch) as a shrinkage value and never had any problems.

BTW, if you add 0.06% to 0.729 you get a diameter of 0.7334.

RRR

[longbow]

Hey Hogtamer... take a look here:

http://www.eazall.com/diecastalloys.aspx#Alloy Description

This says ZAMAK #3 shrinks 0.007"/inch.

I should probably know more about this since I work for a lead & zinc smelter but we only produce raw zinc and lead ingots cast in open face moulds so shrinkage is not something anyone ever worries about or measures. Also, being open face moulds there is lots of molten zinc to replace initial shrinkage.

Anyway, I have to say that 0.007"/inch seems more realistic than 5% and it is in line with what Red River Rick says too.

Here is another link with about the same shrinkage rates:

http://www.brockmetal.com/wp-content/uploads/2014/10/Zinc-Alloy-Diecasting-COMP-LOWRES.pdf

I have to think that 5% is incorrect.

At worst you could cast into an oversize hole in sand or plaster then machine slugs from that core. It would be a bit of work but you would get exactly what you want for testing. Afterwards a mould could be made to suit.

Longbow

[Cap'n Morgan]

The shrinkage rate of 5% is not unusual. I believe it is about the same for lead. The thing to remember is that the sprue (or deadhead) makes up for the shrinking as the cast solidifies. What we boolit casters normally think of as shrinkage is the amount of shrinking from a hot, but solid boolit, to a room temperature boolit. This can be calculated when you know the thermal expansion for the material used and will typically be between 0.5 to 0.8% for lead, depending on the alloy and mold temperature (and mold material):

http://www.engineeringtoolbox.com/linear-thermal-expansion-d_1379.html

[longbow]

Yes, Cap'n Morgan brings up a good point. Lead poured in open moulds shrinks far more than we experience in boolit moulds. Same should apply to zinc.

The figures in the links I gave are for shrinkage in moulds with liquid zinc allowed to flow to replace shrinkage as required similar to what we get in boolit moulds.

Longbow

[Hogtamer]

Ok, so .007 or 7/1000 is the shrinkage to expect in a slug sized boolit mold and 5% or 5/100 is shrinkage in open pour (I'm visualizing pouring into a can)? 7/1000 would be no problem for Tom @ accurate. LB and others, take a look at this page and see what slug you think would cause the fewest potential problems....nothing over 860 grns though...
http://www.accuratemolds.com/bullet_detail.php?bullet=73-770S-D.png

[longbow]

Well, I kinda figure small driving bands might engrave easier with zinc being so hard so maybe 73-770ST tumble lube style grooves or maybe even better, get Tom to leave out the middle band on your 73-770S or make all three driving bands a little narrower.

Maybe someone has experience and can correct me but I have to think that less bore contact would be a good thing with zinc.

Just my thoughts. Of course those thought got a little addled with recoil this weekend too so take it for what it's worth.

Longbow

[Cap'n Morgan]

Hogtamer, the shrinkage when pouring into a can will happen in the center of the cast, leaving a cavity or dimple. The outside measurements will still follow "normal" shrinking rules (0.5 - 1%)

If I were to make a mold for a zinc slug I would probably make the mold a nose-pour design and do away with the sprue plate by making the sprue part of the slug. The slugs could then be cast quickly (keeping the mold hot) and the sprues later be cut with a hacksaw after the slugs had cooled.

I would also recommend several thin driving bands. I use this for solid brass bullets and the driving bands makes up for only about 25-30% of the total bearing surface.

[Hogtamer]

Ok, regrouped and this mold ordered along with Zamak 3 from Rotometals. Put advice here to work. Thanks to all so now we'll see if this works in a few weeks! Our big archery event this weekend so off to "cast" some arrows!
http://www.accuratemolds.com/bullet_detail.php?bullet=73-770ST-D.png

[longbow]

Have fun at that archery shoot! I sure enjoyed ours last weekend. We had four selfbow shooters too so a improvement. Still not a big class but better. We used to get half a dozen or more but most others faded away a few years ago. Good to see some back. Ours was an all traditional shoot but most have those new fangled glass laminated bows and many even use carbon arrows.

Looking forward to your Zlug results!

Longbow

[Cap'n Morgan]

...most have those new fangled glass laminated bows and many even use carbon arrows.

I won't mention my Bowtech compound bow then... I do have an old Sandvik take-down steel bow, though, but I'm hopeless at instinctive bow shooting. Seems my mind and my instinct always starts quarreling each other before letting fly :wink:

[Hogtamer]

140270A few pics from today for you archers.

[longbow]

Nice! Was that an all traditional shoot? I don't see any wheels.

I'd like to see a full length pic of those wood bows! How many selfbow shooters were there?

I do love the look of a nice recurve but I doubt I will ever shoot anything but my straight limb wood bows again. They make me feel like a kid with a stick and string and I have more fun with them than anything else.

Looks like you got a good turnout. How many shooters?

Longbow

[Hogtamer]

Nah, plenty of wheels but the trad guys have all the fun! 10 or 12 selfies at least, a bunch of lam longbows and 'curves but more every year. we set our ranges as realistic as possible and not all wheelie guys are not in love with limbs and vines. Monty Browning is always there with our kids and just got his spectacular book out. Around 250 or so shooters, 400 total counting families that come. Big fish fry tonight, BBQ last night, lunches provided, great camping, all free to participants. All volunteer, ting.mostly church folks. Novelty shoots, many doorprizes and grand prize is hog hunt @ big acreage private land on Savannah River with 7 miles river frontage. Winner determined by Friday team archery poker. 5 people shoot at back of cards on a butt fom 20 yds. high hand wins the hunt. Wish you could be here and join the fun. Big Sunday lunch tomorrow after a church service with Memorial Service immediately afterwords. Then both ranges open for fun shooting.
.

[longbow]

Sounds like a great shoot and good fun!

I think the best turn out of self bows we have had is a half dozen or so. The rest of the field is pretty evenly split between recurves and longbows (laminated bows). We only got just over 100 shooters last weekend but that is one of our best turnouts for the big provincial traditional shoot.

This year we had 4 self bows so at least we had a decent class. Last couple of years there has only been two of us. I would like to see more wood bows out but I really don't care if we have a class. When I am practiced up I can hold my own against the laminated bows. If I do my part my wood bow and self nocked arrows do theirs.

We shoot bowbirds, water bags and long distance for novelties.

The open shoots draw more people but of course most are compound shooters.

Enjoy your weekend!

Longbow

[Hogtamer]

Here's the slug mold Tom's building now.
http://www.accuratemolds.com/bullet_detail.php?bullet=73-770SU-D.png
27% bearing surface. If it all fails I can pour a 1 3/4oz soft lead slug to shoot out of open smoothbore

[longbow]

Now that is a nice looking slug!

If it doesn't work for you in zinc, you might consider having it hollow based. It should make a decent thick skirted hollow base slug.

It might work as is cast of lead through rifled choke tube too.

However, you will be successful with your zinc slug! So don't worry!

Longbow

[Hogtamer]

NEWS! I got the ZA3 from rotometals today, nice shiny ingots in connected pairs, along with a casting thermometer and a bottom pour ladle. I've got an iron Lyman Minie mold that always cast oversize in wheel weights and thought what the heck. First to see if I could melt this stuff on my one burner coleman propane. Nothing for 15 minutes so worked it from the top with a propane torch. Soon got a little liquid and it went pretty quick from there. Meanwhile heating the mold really hot with the torch thinking this will never work with this hollow base pin. Heated ladle too and left in the melt. Ok, ready to hurry hurry hurry, pour and mold quickly overflows and I think it cooled to quick and didn't fill the cavity, but hit the cutter a couple of times with a wooden mallet and this big sprue pops off. Open the mold and can't believe it! Perfect fillout and the minie just fell off the pin. Here you go. The zinc on the left and .004 less diameter less than the lead, .575 vs .579. Somebody help me here but is that not .0069%? So if my new mold cast .735 w/COWW won't that be about .729? And then there's the weight. The lead minie weighs 478 gr. vs 280 gr. for the Za3, 58% less. Now I see there's a void in nose up from the bottom, that may or may not be a problem. Can't really tell without cutting or drilling how much metal is missing there
140651. Overall greatly encouraging.

[longbow]

Looks good! What does it mic compared to lead?

You will get more shrinkage in 12. but it will give you an idea of what to expect.

Now let's see some of those big 'ol 12 ga. boolits! The mould must be on its way shortly so don't dilly dally when it arrives.

Longbow

[Hogtamer]

edited above post.

[longbow]

I stand corrected in my comment "big 'ol 12 ga. boolits" Of course I meant big 'ol 12 ga. Zlugs!

And yup it does look promising. You should be right on for size. Oh, wait a minute, these are intended for rifled gun right? What's the groove diameter? Seems to me they tend to be a couple thou under the nominal 12 ga. bore of 0.729". Not much bearing surface to swage though so that's good.

Anyway, I will be looking forward to casting tests in the new Zlug mould.

Longbow

[Michael J. Spangler]

I cast some zlugs using a lee 1 oz mood yesterday.
I will get some measurements and picture later. I hope the info is helpful. It cast very easily. I used a Rowell 1# ladle and cast from a cast iron pot on top of a turkey fryer burner. I ran the metal at about 725 degrees. Once I cast a couple slugs they dropped fine and as long as I got to the sprue quickly I had no issues cutting them. It was just like casting with that lee mold with lead. Keep it moving fast and all is well.

[Hogtamer]

Thanks Michael. I got my mold yesterday from Tom @ Accurate molds....1 week from order date including shipping! First cast was from COWW to actually see what it dropped vs specs. Well, when Tom says .735 that is exactly what he means apparently! Dead on. Good crisp grooves. Supposed to weigh 770 grns, 3 slug average = 775 grains, about 1 3/4 oz. So Tom has done his part to perfection! Hate to think what it will take to move this baby. Next of course will be casting with the Zamak 3. Stay tuned!

[Michael J. Spangler]

Awesome can't wait to hear the results.
I have a friend that has tested some of my lead lee slugs and he used to load 2 of them back to back in a 10 gauge hull. That made for some nice recoil.

[longbow]

Those look real good Hogtamer.

Let's hope that the zinc shrinkage is what we expect then you are off to the races.

Looking forward to field test results.

Longbow

[Hogtamer]

Zlugs! .729 - 465 gr. Zamak 3

[Hogtamer]

Casting was no big deal, just have to get big puddle on sprue, shake mold while you're pouring over pot and let excess run over into pot. Now the bad news. I got exactly what I'd hoped for but takes too much pressure to engrave. I tapped both the lead and the zinc slugs through an old sawed off barrel I have to "size," and close as I can tell the slugs are exact same dimension, .729 afterwards. Took more pressure than I thought to get the lead slug down the pipe of the rifled barrel but got perfect engraving. Can even see tiny bit of light at the grooves when halfway down the bore. Exact same thing picture with the Zlug, but couldn't get it down the bore with a hammer and wooden dowel. Finally had to knock it out from other end. Did engrave the zlug but this stuff is hard. Won't shoot it from rifled barrel needing that much pressure. Thought about freezing them to contract but would that be a real fix? Maybe could make a sizer and take off another .001 - can barely hook fingernail on rifling now. Would lube help? I need you guys here as this seems real close. Talk to me!

[Y-man]

WOW! The most expected result I have been waiting for... Great Zlugs there...
I can only dream about such perfection.

[longbow]

Hogtamer, you are so close!

I would try lube. Lee Liquid Alox would probably be perfect but I have to think that any boolit lube would work.

What you might think about is to load some up and send to Tom Armbrust for pressure testing to see how they do. I think his prices are pretty decent or last I heard anyway. I know Greg Sappington has gone to Tom with some of his loads before.

How much force did it take to engrave? Can you put a scale on when you push through the bore? I am thinking that if it takes say 100 lbs. to engrave, that seems like a lot when you are pushing/hammering but when you have 10,000 PSI pushing it may not be so much.

Greg says that zinc is so hard that zinc boolits cannot be easily sized... which isn't to say they can't be sized but it may take an arbor press to do it.

If all else fails I will make you a hammer sizer to drive them through. It may be tedious but it should work fine. Or possibly a roll sizer would work. I am thinking like the Corbin knurling tool but with smooth rolls. If you send me a few slugs I will give that a try in my knurler. I can make up smooth rolls and give it a go.

We have to get you Zlugs that will work at safe pressures.

So, first try contacting Tom Armbrust:

Tom Armbrust
Ballistic Research
1108 W. May Ave
McHenry, IL 60050-8918.
815.385.0037
E-mail - barbmiller49@yahoo.com

Not sure if that is current but the best I could find. If it doesn't work Greg Sappington likely knows how to get hold of him.

If that fails, send me some zinc cylinder anodes and I will size them and send them back to you.

Longbow

[Hogtamer]

Good point about the engraving pressure and good idea to get them tested. I will make that connection. One thing good though, I wouldn't hesitate to send these down a cylinder smooth bore on top of an x12x gas seal and some hard cards. That may be right up your alley! Also thinking about a drill centered in the base to take some weight off the back and make it more nose heavy. BTW, am measuring with a caliper so could be off a thou or two. Really appreciate the offer and I will definitely send you some zlugs. Was gonna send you a few archery trinkets anyway from last weekend and tomorrow is my first day off since then, so look for a package soon. Some experienced eyeballs and hands on these things may pay off for us all! Thanks a million. Oh, found a RCBS iron .610 RB mold and will be trying to make a 2 - ball load in lighter weight too. Got a great lead 2 - ball but it kicks your brains out. brains out. brains out....

[longbow]

Was than an echo I heard....?

[Cap'n Morgan]

Hogtamer.

While zinc may seem quite hard compared to lead, it's not harder than solid copper and brass bullets. I wouldn't hesitate to try them... but I might just use a long string to pull the trigger the first time :wink:

[Tackleberry41]

Was gonna ask how a Lee 1 oz slug mold works w zinc, but see somebody already tried it. Been keeping an eye on these zinc threads since just a good thing to know how to do. But a Lee 1 oz slug will only be about half an ounce in zinc, guess that messes up the load data a little.

[longbow]

Tackleberry41:

A bit of judicious turning of the core pin in both diameter and length would add some mass so if for use in a rifled gun not really a problem. I'd bet you could get weight up to 7/8 oz. anyway.

Check out BPI's "Load of the Week" they have many light payload high velocity recipes. Could be just the ticket.

Cap'n Morgan:

That string wouldn't stretch from Denmark to Georgia would it? That would certainly get you out of the blast radius but the drag on the string might be a bit much.

Just kidding! I agree about the hardness and in a tumble lube design there is not a bunch of metal to swage. Safest approach though is to get them pressure tested if possible/practical and second is the long string. I suspect that while it may seem like a lot to engrave them that the 10,000 or so PSI behind them and the jump through the forcing cone (momentum) will engrave them just fine. Once engraved they should slide nicely down the bore.

On that note, I am guessing a powder at the slow end of the burn scale would be the best choice so pressure doesn't spike during engraving. In fact IMR4227 might be a good choice there but I wouldn't want one of Ed Hubel's recipes behind a Zlug for its maiden voyage. That might be a wee bit much.

Longbow

[Hogtamer]

Update: I sent a couple down the pipe of an 870' cylinder bore 2 3/4" over 33 grns of Alliant Steel powder, an x12x gas seal, couple of hard cards and a felt wad, roll crimped. Modest recoil, guesstimating 1600 fps. Nice load. Blew through 3 pieces of 1" particle board @ 50 yds. Got you a package in the mail today LB. Have your way with those zlugs, got plenty more!

[Michael J. Spangler]

the lee 1oz slug mold drops at about 260 grains and .675 in zinc wheel weight alloy.

[longbow]

What size do you want them after I have had my way with them?

I will make them whatever size you require then send them back your way.

[Hogtamer]

Per Capt. Morgan, included a length of string! Seriously though, thought perhaps you could test them out of smoothbore, examine and measure the one I engraved in my barrel, share your thoughts and experience; if you have access to a rifled gun make 'em fit and give them a whirl. I've got a machinist buddy who could make a type of hammer-through sizer if that's what's needed.

[longbow]

I certainly don't mind flinging a few downrange from smoothbore but without an attached wad they won't be stable very far... but then who said I couldn't try attaching a wad.

I will check them out and see what's what. Don't think I have access to a rifled gun anymore though. I may just get back to my rifled choke tube and finish that up. My intention is deep wide grooves, narrow lands and slow twist but Zlugs might just work in it.

Yeah, making a hammer sizer shouldn't be much work. Just bore to the size you want, make a punch and have at 'er. A bit tedious but for a few to try not a lot of work to make or use. I don't mind sizing and sending some back. Whatever suits you.

I will be looking forward to the package of Zlugs... wait nothing remotely firearm oriented so cylindrical zinc anodes is good.

Longbow

[Hogtamer]

Zinc Lugs... for your hobby cars. And a knap box. And a book about another kind of "cast."

[Tackleberry41]

Tackleberry41:

A bit of judicious turning of the core pin in both diameter and length would add some mass so if for use in a rifled gun not really a problem. I'd bet you could get weight up to 7/8 oz. anyway.

Check out BPI's "Load of the Week" they have many light payload high velocity recipes. Could be just the ticket.

Longbow

A lathe goes a long way with those pins. Modified the one for the .575 minie mold Lee sells. It drops a bit heavy for use in a 20 ga, but might work as is with zinc. The weight is not far enough forward, new pin solves that, deeper cavity. Wish they made something similar for the 12ga. Guess the mold could be modded to make it flatter vs round, more weight. Just wish those handle pins came out easier. Guess solution is to drill them out and put in a screw. Be nice if the small lee molds could have handles removed, I can fit a while lot more Lyman or other molds on a shelf than I can lee.

Has anyone tried to buy that extra pin carrier plate from Lee, vs making one for use with making hollow point molds?

[Blood Trail]

What alloy did you use besides the zinc? Reason I asked is because I have a bunch of kirsite (sp?) I'm not sure what to do with.

[Blood Trail]

Never mind, I saw it!

[Blood Trail]

140270A few pics from today for you archers.


Nice! Was that an all traditional shoot? I don't see any wheels.

I'd like to see a full length pic of those wood bows! How many selfbow shooters were there?

I do love the look of a nice recurve but I doubt I will ever shoot anything but my straight limb wood bows again. They make me feel like a kid with a stick and string and I have more fun with them than anything else.

Looks like you got a good turnout. How many shooters?

Longbow

I, too, am a bow hunter. I shoot everything from wheel bows to primitive. I'm in the process of making a boo-backed Osage self bow using all natural materials. Even the string is hog gut.

I made some arrows out of river cane. My knapping skills leave a lot to be desired, but I just started. I usually make my arrow heads out of scrap metal I save from making knives.

Killed a deer last year with my recurve and an arrow I made.

This year, I wanna go 100% primitive.

http://images.tapatalk-cdn.com/15/06/03/ad75ddff26e00ef57ffe5d22673319db.jpg

http://images.tapatalk-cdn.com/15/06/03/1e5f68e9d1cab09fc7fdd8002139a222.jpg

http://images.tapatalk-cdn.com/15/06/03/56a1b7137e1d59ab03d5291a07272151.jpg

http://images.tapatalk-cdn.com/15/06/03/50f51143ac29fc4210f47b5822394128.jpg

http://images.tapatalk-cdn.com/15/06/03/9a0a8566309379feb282cdf7f97e8857.jpg

Sorry to derail this thread.

[Ballistics in Scotland]

My first thought about this project was that it could make a fine project for a firm with die-casting equipment. But I am very pleasantly surprised to see such promising results from gravity casting.

Why not commercial die-casting, since so many states require shotguns for deer, and nobody seems quite satisfied with the performance of existing slugs? I thought they would require a range of different diameters, to suit the different diameters we find in even modern shotgun barrels, and maybe they would be afraid of product liability trouble with members of the intellectual classes who get that wrong.

I would be very wary of much greater forcement than you would find with lead, especially since it comes when a shotgun is at its most vulnerable, immediately the weakening front of the chamber is exposed to pressure. It sounds like a mould with fewer or narrower driving bands might be better. With the mould you've got, though, there has to be a diameter to which these things could be sized, and still get enough grip on the lands to spin them. WE Metford found that rifling half a thousandth deep, and even spiral scratches made with coarse abrasive on a lead lap, would spin a hard-cast bullet until it eroded smooth. The trouble with gaps at the grooves isn't lack of grip, but the blast of gases through the grooves, which tends to blast atomized lead ahead of the bullet, where it is ironed into the bore surface. Besides, atomized lead is something you don't really want to be around. I don't think either of these problems would be as bad with zinc, and it may be that a firm grease cookie between card wads, or a thick plastic wad, would close off those gaps. I can't see this problem being anywhere near as insoluble as it would be with a modern high-pressure rifle.

If it couldn't be solved that way, what you need is a groove-matching-bullet 12ga muzzle-loading rifle, and a piece of the barrel blank to make a mechanically fitting bullet with all the force it takes. Everybody should have one...

I have a rather obsessive interest in Robert Hardy the actor's "Longbow", which almost uniquely combines history and technology without falling down on either. He is not only a traditional archer and bowyer, but a member of the "Mary Rose" trust, specializing in the study and conservation of the Tudor bows found on the warship of Henry VIII, which was raised from the mud outside Portsmouth harbor.

When did I become interested in this? Shortly after my encounter with myasthenia. If you must have a serious illness of the nervous system it is the pick of the bunch. There are no symptoms except extreme weakness, it hardly ever kills anyone, it goes very nearly away, and a recently developed operation stops its once inevitable return. Mine left me with a weakened left hand and both triceps, which are the most unnecessary large muscles in the body. Gravity will do practically all the things the triceps can do, except draw a bow.

I corresponded for a while, about fifteen years ago, with Jim Fetrow of Oregon, who makes bows from native yew, and even then had shot sixteen bull elk with all arrows passing completely through. A friend has successfully grown an illicit cutting I took from the great Anchorwyke yew at Runnymede, under which the Magna Carta may have been signed when it was a large tree. You can never tell the age, because those very old ones are always hollow. My disability lets me out of waiting a century or two. But I have designs, for my own garden, on one in Scotland which is surely much older.

[Blood Trail]

Brother Scotland,
I'm very happy with how factory slugs like Remington Accutips performs out of my slug gun.

But if I can duplicate or at least get pretty close with the Lee slugs and sabot slugs I've been messing around with, that would be better.

Plus, we all love to tinker!

[Hogtamer]

Yep, that cane arrow will definitely make a Blood Trail. That's hunting brother. This gun stuff is kinda grocery shoppin! Sure is fun though.

[Hogtamer]

Just got back from a machinist buddy's house, had in mind him making me a sizer. Well, he measured the zlugs with a real instrument and the actual diameter is .7275. The engraving on one I hammered up the breech a ways was .724. He must be related to Cap't Morgan 'cause he said shoot 'em! Gonna wait on a 2nd opinion from LB all the same. So let's look at some prospective loads. I shot a couple out of cylinder bore yesterday, used 3" Rem Nitro hulls that I'd loaded several times, cut the crimped ends of and roll crimped to a 2 3/4" finished load. I've got some experience with Steel powder under Ed Hubel's guidance, also looking a steel shot loads using equivalent weights. 465 gr is about 1 1/16 oz so I used 33 grns Steel powder, x12x gas seal, fed. 209a primer, a couple of hard cards and a felt wad. No problem with that I think. I will be using new 3" Win. Hulls in working up these loads. I see I need to lose the felt wad when roll crimping. Is a column of just hard cards ok? I also have 700x, 800x, and Longshot. Oh, and have a Hastings barrel bought from Littlejack on the way for my 870.

[longbow]

You may be a bit disappointed in my answer Hogtamer. I still lean toward pressure testing them. Alternately I would try sizing or turning them down until they don't take much if any more force to engrave than lead slugs.

And of course if you have a sacrificial shotgun, the string method works almost as well as pressure testing. If the gun goes "BANG" and doesn't come apart then you can check for sticky extraction, case head expansion, etc. If none shows up the load should be fine.

However, I tend to play it safe after having had one shotgun come apart in my hands. Not a bunch of fun and I wouldn't wish it on anyone. I was very lucky and only got minor scratches and some hearing loss.

Longbow

[Hogtamer]

LB, no disappointment here, that's why I'm waiting for your hands on inspection. No risk in the cylinder bore as it was an easy push through out of the barrel I shot.

[bikerbeans]

Hog,

I have a rifled barrel 12ga handi that I will volunteer as a guinea pig for testing your Zlugs. I have a remote trigger operator (30'
of parachute cord) and a milsurp flak jacket.

BB

[xacex]

Hmm. Anyone try a Lyman 525 with Zn yet. I would much rather use Zn vs all the lead I have been using. Maybe make a plug so it is a solid base to bring the weight up? I have Zn, and a mold but I need some ideas to try.

[Electric88]

Is the consensus right now for zinc shotgun slugs that they will work out of smoothbore, just unsure about rifled barrels?

[ohland]

I read the thread, but I didn't see any paper patch or the crushable sabot wads (like accordian ribs all the way around the wad, er, skirt, whatever...

[Hogtamer]

Well, they will shoot out of smootbore but accuracy is untested. Longbow will certainly try some as will I next week.

[Hogtamer]

BB,
You've got a deal! PM me your addy. I need all the quality input I can get and you're a likely suspect.

[longbow]

Without drag stabilization there won't be any accuracy out of a smoothbore... well, anymore than a few feet from the muzzle anyway.

However, with the addition of an attached wad there is a possibility of some accuracy anyway.

I won't likely bother shooting naked Zlugs out of my smoothbore just to go "BANG". I will attach a wad of some description then give that a go. Then there will be a "BANG" and some potential accuracy. I will also use some end grain wood or other stopping material to check penetration as well. I'm betting a Zlug will shine in the penetration department.

Longbow

[Electric88]

I'm excited to hear results about doing this! I am interested in finding out what wad is used and the effect, and will be following closely!

Keep up the awesome work guys!

[Hogtamer]

Just talked to Tom Armbruster @ ballistic research. He's intriqued by this project too. I will load 3 each of 2 or 3 different charges and he shoots them. Rocket science on his end but not mine! He will be shooting them out of a Hastings barrel too. He can make recommendations based on the results. I will get these off next week some time. Man this is moving along! Thanks for all the good advice and encouragement.

[bikerbeans]

The Zlugs have arrived! Range report soon. I was preparing my shoulder for this project by shooting 650g boolits with my 50-90 this morning.

BB

[Hogtamer]

Hey BB, the point of this whole exercise is to produce a full bore slug that does not dislocate shoulder! 50/90????? Sheesh, hurts to think about it. I'm getting a package to Ballistic Research this week with 3 each of 4 loads: For the Zlugs loads of 34, 37, and 40 grns. of Steel in 3" Winnie Hulls, a Fed. 209a primer, an x12x gas seal and 3 hard cards, roll crimp. Also a zinc .600 2-ball load that weighs about 15/16 oz w/ 42 gr Steel that oughtta be pretty snappy.

[bikerbeans]

Progress, loaded 10 Zlugs tonight. Load #1, 35g blue dot, (1) x12x gas seal, (4) .125" nitro cards, fed 209a, win 2.75" AA hull, roll crimp. Load #2 is one nitro card, 60g sr4759 other items same as load #1.

I engraved a slug in my rifled barrel with a ball peen and half inch dowel rod. Very light engraving and it only took very light strokes to tap the zlug down the bore. Me thinks my barrel is a tad on the overbore side. FWIW, it was harder to drive one of turbo's fullbore slugs down my barrel than the zlug.

My scales said the Zlugs weighed 1 1/16 ounce, or just over 30 grams for our friends on the other side of the "pond".

BB

[longbow]

I still haven't received my Zlugs yet so have at 'er BB, you are in the lead and have a rifled gun so more interest for more folks.

It will be interesting to see how they do but if engraving was that easy I doubt pressure will be an issue. Even if the Zlugs are a bit undersize for your barrel I am betting they are hard enough that they center up and do okay... as long as you have a good gas seal ~ I don't see mention of a gas seal. I found I got significant leakage in loads using nitro card wads and no plastic gas seal not long ago.

Longbow

[elvas]

Hogtamer,
I have found that X12X gas seals are usually destroyed at firing leaking gas in the slug area, even with slow burning powders. Actually the only gas seals I found that work satisfactory are those cut from a standard lead shot wad (overpowder cup only).

[bikerbeans]

LB,

I edited my post to include the gas seal I used.

I am not too concerned with pressure in this particular shotgun as the bore is a bit large and I am using starter charges (for a 600g fullbore slug) of powder. I have decided to pass on testing Unique, too fast a burnrate.

BB

[Hogtamer]

This is reminding me of the first time I launched my big wooden boat I built 15 yrs ago. Anxious a bit, hoping for good results. Nothing to do but point it in the right direction and give 'er the gas! LB, I thought the postman would have wandered your way yesterday, package went out on the 1st.

[bikerbeans]

I fired two 12ga Zlugs this morning in my fully rifled H&R. Both the gun and I are alive and well. Both Zlugs went through about 8 inches of OSB and then dug a furrow in my barn floor, a mix of limestone screenings, gravel, dirt and sawdust. I found one zlug and I am sure I could reload it. I am still looking for the other slug. I will make a range trip shortly with the chrony and some targets.

BB

[Hogtamer]

BB, you da man! And that was a starter load?!!

https://m.youtube.com/watch?v=QAnky-QJwII

[bikerbeans]

Fired Zlug, 60g SR4759.

BB

[longbow]

Hogtamer:

I hear criticizm of your USPS for slow service but I can't believe how fast USPS is compared to Canada Post!

Greg Sappington sent me some stuff and it was across the continent and waiting for me in a Washington post box in something like two or maybe three days. Canada post on the other hand regularly takes two to three weeks to get a letter from Castlegar to Vancouver (about 8 hours West) or Castlegar to Calgary (about 8 hours East). It takes a week to get a letter from Castlegar to Trail (about 20 minutes South).

Their record for me was a cheque to an archery store near Calgary and it was 21 business days!!!

And the cost! I can't recall for sure what it cost me to send you the 0.678" balls but IIRC $16.00!!!! And I know I shipped some Maxi's to a friend in North Carolina and that was $16.00 for I think twenty five 370 gr. .50 cal. Maxi's.

I would trade service and cost of USPS vs Canada Post any day!

I suspect the package of lead anodes is being held up in customs before Canada Post even gets their hands on it to slowly deliver it. No doubt routed from the customs to Toronto, then Vancouver where it will sit and finally get loaded to come to Castlegar.

Frustrating it is!

Okay then, rant off... simmer down.... breathe deeply... there, I am like a hollow reed and the wind blows right through me.... aaahhhh, better.

I want those Zlugs! Mind you, if I do not have them for this weekend it will be a couple of weeks before I can load and shoot.

Good to see BB is alive and well and the zlug did real good! You guys will have testing complete before I even get mine.

Longbow

[Hogtamer]

I just got my loads boxed up to send to Tom Armbrust tomorrow. LB, just between you and me, why ya reckon BB was shooting at his barn? And he never said how long his string was!

[longbow]

Good point! I had assumed the 8" of OSB was a backstop but...? Maybe he was outside the barn when he pulled the string? A barn should contain shrapnel if the worst happened.

Since I am shooting smoothbore I shouldn't have anything to worry about.

I was just thinking about a wad to attach and remembered that my order to Will Bilozir has not been completed yet. He didn't seem to know what the special "gas seal" was that BPI is listing. A couple of those screwed onto a zlug should make a nice Brenneke style. They are 1/4" thick plastic and have a hole right through the middle (not sure how that qualifies them as a gas seal but...).

I better get hold of Will and get that order sorted out.

Longbow

[bikerbeans]

LB,

No string for the testing. The Zlugs went down the bore easier than the fullbore slugs I usually shoot so I wasn't worried about pressure. I am not expecting much in accuracy as I think my bore is way oversized for the Zlug. I can't see any engraving on the fired Zlug. My barrel has a long forcing cone and there is over an inch of jump to the rifling, maybe the Zlug is being "sized" and not rotated when I fire the gun? I will find out tomorrow at the range.

BTW, I have replacement cost insurance on my barn so I don't mind shooting at it.:wink:

BB

[cpileri]

looking forward to range report!
C-

[Greg5278]

The X12X is usually ther best Gas seal for Slugs. Maybe Your Wad Column was not sturdy enough.
Zinc is not that Hard to Load, it does not need Lube. If You need to size it, make a Die set and use a Bench Vise ot Arbor Press to push it through. It will go through fine, just put a taper before the sizing section, and a Relief cut after.
A few Thousandths of Extra won't hurt anything.

I design my Brass and Copper Slugs to have a reduced bearing Surface and Shank Diameter. The Brinell Hardness is Similar to Zinc. I make the Bullet Shank a few Thousandths smaller than the Land Diameter. The fired Slugs do not have any Marks on the Shank, unless fired in a tighter bored Gun. If Loaded up gfast some Zinc Slugs will penetrate 5/16 1018 Mild Steel Plate.

Given the weght Difference with LEad, I would stick with Middle of the Road Burn Rate powders. Unique is too Fast. Alliant Steel may give You too much Muzzle Flash. I seem to recall using IMRT 4756 for a lighter Zinc Slug, and VV340 or 350 for a heavier one.

Maybe try a BP12 or BP12 Tuff Wad for a Ribbed Sabot if Using a much smaller Zinc Slug. I seem to recall the Russians doing some thing Similar with a Steel Slug in a Ribbed Wad.
Greg
AKA 12 Bore

[longbow]

Well, I have to think that my rant on Canada Post caused a rip in the space time continuum which resulted in a time warp around Canada Post... the zlug package arrived today! This is record time I have to say. Hogtamer said he mailed it on the 1st so only 9 days across the continent and across the border. Impossible I would have said if I wasn't staring at some shiny zlugs, two beautiful knapped arrow heads and a nice book. Very generous Hal. Thank you very much. I have the Witchery of Archery by Maurice Thompson so Toxophilus in Arcadia will be a nice addition.

I do in fact have a couple of appropriate arrows made out of black locust shoots. Neither is without wobbles and small knots but when straightened they both spin around their centers as well as any dowel shaft and they shoot well. They will lose their current field points and have some nice knapped arrow heads hafted to them. Of course they will not be shot with the knapped arrow heads unless possibly at game. For now they will reside on my living room wall as art work. I will post photos.

On to the zlugs. I will not likely have time this week to get attached wads made up for them to shoot this weekend (maybe but not likely) but will certainly mic them and check fit though bores, etc. It will be a couple of weeks before they are likely to be shot and I want to do it properly. I can always make a bang but I want a bang with accuracy so will do this as best I can.

I have Blue Dot and SR4756 which should both be good powders for this weight of zlug.

Looking at the engraved zlug you sent I have to think that these would be just fine pressure wise as the engraving is quite shallow. However, best to play safe and have Tom pressure test them. I don't know what he is charging these days but I have no problem putting some money towards the testing as we are all benefiting so let me know if I can help out.

I will try to get the testing done ASAP but I have to drive my wife to Vancouver (8 hours away) next week to see a specialist and won't be back until the Saturday evening so not much time between now and then. After that I will have some time.

Again Hal, thank you for your generosity.

Longbow

[Hogtamer]

I will be thinking and praying for your wife's good health and the zlugs can wait. BTW, there is a white point in the box too, easily overlooked. May be knapped from a piece of very rare "commode stone!". And as you know, if both ends of those arrows are pointing a staight line the middle will follow!

[bikerbeans]

HT,

Was the "commode stone" mined from above or below the water line?:kidding:

Zlug range trip pushed to Friday.

BB

[Greg5278]

Longbow, Maybe send Him some nice Obsidian from BC to Knap. It takes a really nice edge, and flakes well.
It comes in pretty Colors too.
Greg
AKA 12 Bore

[Blood Trail]

I have some sabots by slugrus if anyone needs to experiment with. They fit .50 cal slugs.

I contacted BPI and sent me a sample pack of gas seals. 10 each to be exact

[Hogtamer]

BT, how did those slugs shoot for you? I inquired about buying a bunch of the sabots but no volume discount at all and they were kinda pricey. Seems like you could load 'em pretty hot. Did you use their slug or a .50 cal you cast?

My Fedex to ballistic research just got picked up today, so it will be middle of next week before I can hope to get any results, prolly longer. So BB, you're carrying the ball this week. Thanks!

Greg, thanks for checking in with this, I know you've got a lot of experience with "non-traditional" loads. I wish I had thought to load a couple with Longshot and 800-X to send along, as you're right on about the muzzle flash from the Steel. Now the wait for any degree of accuracy.

[longbow]

Hogtamer:

Right you are then so another thanks!

That commode stone point is also extremely nice. It was hidden under a flap of padding (toilet paper...!?!).

Greg:

If I can find some obsidian I would be happy to send it. All we seem to have around here is quartz. I have as yet to find any form of volcanic glass.

I was working on a project for the Hanford nuclear site in Washington to vitrify nuclear waste. The result looks very much like flint or obsidian. I have a few small pieces (no, not radioactive) from test melts using simulants. A local knapper tried it and said it knapped like obsidian. (Now that I say that, I will ask where he gets his material. I do not think locally.)

Had the project continued I would have had an unlimited supply of man made volcanic glass. The basic procedure is to use high current through large graphite electrodes to melt "dirt". The preferred "dirt" is local soil that has high silica sand content. The result is molten rock much like lava that when cooled forms a flint/obsidian like glass.

However, I digress from the topic of zlugs.

I am going to try to get at least a few attached wads made up and possibly shoot this Sunday. I would like to shoot anyway, though time is limited, and I want to contribute in a timely fashion as well.

I will do the best I can.

Longbow

[Michael J. Spangler]

i had a buddy try out some Zlugs from my lee molds.
He loaded them over a charge of red dot and loved them. he said they shot flat and hit like a hammer. the plug smashed rocks on the berm and the recovered slugs look like they could be loaded again.
cool stuff

[Blood Trail]

BT, how did those slugs shoot for you? I inquired about buying a bunch of the sabots but no volume discount at all and they were kinda pricey. Seems like you could load 'em pretty hot. Did you use their slug or a .50 cal you cast?

My Fedex to ballistic research just got picked up today, so it will be middle of next week before I can hope to get any results, prolly longer. So BB, you're carrying the ball this week. Thanks!

Greg, thanks for checking in with this, I know you've got a lot of experience with "non-traditional" loads. I wish I had thought to load a couple with Longshot and 800-X to send along, as you're right on about the muzzle flash from the Steel. Now the wait for any degree of accuracy.

Brother, the blue sabots did great with almost every powder I tried. My chronograph broke and I got a new one, so the next trip out to the range, I'll document better.

However, the sabot wads from Slugsrus shot horrible out of my mossberg 835 rifled barrel. I was finding the sabots every random place you can think. I even found one about 30 yards to the right of the target I was aiming at. The holes on the target (the ones that hit) where oblong in shape. Strange. Only one load look decent. It was 34 grains of Longshot under a 350 gr XTP.

Upon further investigation, slugrus sabots aren't designed to be shot out of a ported barrel, which mine is, according to their website.

I found a website that does custom slug molds. I will order one once I can figure out (with y'all's help) on which direction to go.

I'll post pics of those slugrus wads in a few days. Headed to east Texas to kill some pigs.

[bikerbeans]

Gilda Radner was right, it's always something. The trigger on my H&R decided to fail this morning. I had the gun cooked and on target and just before I put my finger on the trigger the gun went off. Plan "B" is now in effect, a good friend is letting me borrow his H&R USH.

I did chrony two loads before the trigger failure. The gun is an H&R Tracker II with an 18.5" fully rifled barrel.

Zlug, 35 grain blue dot, 1271 fps.

Sticky extraction and a very slight bulge at the extractor notch.

Zlug, 60 grains SR 4759, chrony incorrect, 1370 fps with 24" barrel

Extraction normal and the hull looked fine.

I know two data points are close to useless. From past testing I would expect 100 to 200 fps velocity increase in the 24" USH.
I hope to have the USH within a week.

BB

[Hogtamer]

I know slug shooters can flinch from time to time didn't know a gun would! You must have shot some big loads out of that H&R over the years and got it slug shy! Did you hit the target???

[bikerbeans]

HT,

I don't shoot groups when I chrony a load, just make sure I aim to put the projectile correctly over the sensors. This technique has allowed this chrony to have a long life.

BB


I know slug shooters can flinch from time to time didn't know a gun would! You must have shot some big loads out of that H&R over the years and got it slug shy! Did you hit the target???

[BAGTIC]

.5 to .8 % is .005 to .008 inch per inch.

[Hogtamer]

In lieu of news, how about this for the shotgun forum theme song?
https://m.youtube.com/watch?v=fCIw6QCmaJ8

[Hogtamer]

My loads were delivered to Ballistic Research today, so hopefully results this week. In the mean time I tried to gey a Zlug down my hastings barrel with a 2 lb. hammer and a 5/8 dowel.....no luck! Mine's tighter than yours BB! The 1st shot will be with a string no matter what Tom's test shows!

[NoAngel]

I realize not everyone has access to a lathe but were I to take on this sort of project, I think turning them would be much easier in the long run. Certainly cheaper. Zinc will inevitably wear out spru plates.

[bikerbeans]

HT,

The groove diameter on my tracker II is over 0.7315", I don't have a large enough slug to get the exact dimension. I am hoping my friend's USH 12ga has a tighter bore.

Can you PM me the contact info for the pressure testing? I am curious about the pressure of several of my SR 4759 loads.

BB

[Hogtamer]

News from testing this evening as Tom called with results. The biggest load is a good starter! The highest pressure from 40 grns Steel was 7900 psi, a couple lower. (my roll crimping needs more consistency, depth gauge broke on drill press) Velocity was about 1600 fps. His presure barrel is a bull 1 1/4" Hastings 24". He thought a faster powder, maybe 800x would be better. He wasn't testing accuracy but did say all 9 shots seemed to go into a couple inch hole in berm @ 50 yds. Mentioned muzzle blast of Steel could effect accuracy as Greg pointed out. SOOOO, I'm gonna give it a go out of my gun, prolly Monday. Biggest problem with that is temps are running triple digits here for the next several days and this is supposed to be fun! And I hope to come up with some way to retrieve slugs. Will load some 40 and 43 grns Steel and some 800x.
Today
Jun 21
Mostly sunny and hot
98°Lo 76°
more
Mon
Jun 22
Mostly sunny and very hot
99°Lo 75°
more
Tue
Jun 23
Mostly sunny and very hot
99°Lo 77°
Wed
Jun 24
Mostly sunny and very hot
100°Lo 74°
more
Thu
Jun 25
Partly sunny and hot
96°Lo 75°
more

[Ballistics in Scotland]

I must admit that that experience with the 2lb. hammer would have put me off. But that pressure figure, from a professional tester, is extremely reassuring, and the velocity and accuracy seem very adequate. I suppose it was a Hastings barrel of the same diameters? The only land diameter I know of them having was .716in.

Now on a slightly different tack, I think that for smoothbore slugs the natural comparison is with round ball which, if not allowed to roll or deform, can be surprisingly good. Apart from non-deformation, the main reason for using zinc is to have high velocity without excessive recoil. So what about 23/32 ball bearings? I think this is about the cheapest on eBay USA at the moment, and for the infrequent deer hunter they compare pretty well with a mould. 3/4 in. should be fine for 10ga.

http://www.ebay.com/itm/110-Pieces-of-7188-23-32-Chrome-Steel-Ball-Spheres-/111149116920?pt=LH_DefaultDomain_0&hash=item19e100edf8

[longbow]

I am back from Vancouver after the trip to the doctor with my wife so now have some time... other than I am teaching a friend to build a wood bow and my kids are coming to visit next weekend for a few days. However, this is the least busy I have been for some time.

I have not yet checked fit for the smoothbore but I suspect it will be loose if anything. If so I will knurl to size.

I found some 1" thick polyethylene that I will use to make attached wads for the test.

I suppose it is a bit anti climactic to be testing so late into this but I will carry on.

My hope is that the hard zinc will resist deformation in the barrel and if I make wads correctly that there will be some acceptable accuracy. Time will tell! I hope to be testing within the week. I may have to use 3" hulls to accommodate the slug and lengthy attached wad. However, I have a few so if required that is what I will do.

Good news on the pressure test results too! I have to think that the jump to the rifling allows easier than anticipated engraving through inertia. Good to play it safe though.

This is getting kind of exciting and I am thinking about my yet to be finished rifled choke tube as well. Zinc would undoubtedly take the rifling better than lead when slug meets rifling at something like 1500 FPS. I had not thought of that before Hogtamer got this zlug thread going.

Thanks for persisting and sharing Hal.

Longbow

[cpileri]

Great news Hogtamer!
Please keep us posted.
C-

[Hogtamer]

142646.
142647

YAHOO!!!!!!!!!! Fellas, it works!!!!! I just launched 5 ZLUGS out of an 3" 870 Express with a Hastings 20" rifled cantilevered barrel (5 lands) and a Nikon prostaff slug scope, and the results could not have been better!

Load: New 3" Win Hull; Fed 209a primer; 42 grns Steel powder; (1) x12x BP gas seal; (1) BP 1/2" hard card wad; (2) BP 1/8" hard cards; 465 gr ZLUG; roll crimp

Shot off a lead sled and YES, I used a string to launch the first one! (pic) Recoil moved the sled back about 3". After getting Tom's results was very comfortable using 42 grns Steel. Also from results, guesstimating about 1700 fps and still moderate pressure. Got complete burn, not a mark on the hull, not even residue on end of hull. Action opened about 1/2" and brisk ejection.

Distance: 25 yds
Target: an old cooler, interior dimensions 32" x 21" x 12" filled with water (big marine cooler). (pic). Had not shot gun since replacing barrel and transferring scope from receiver of gun to cantilever mount on new barrel. Windage was still on but elevation way high. First shot missed high completely. Next 3 I couldn't make myself shoot low enough and all went full length through the lid. Finally held about 18" low and got a good strike.

The Zlug penetrated full length through the water, came out the back spent and rolled off the table the cooler was sitting on and onto the ground. Except for engraving on Zlug that you can barely hook a fingernail on it is pristine. (pic, fired Zlug on left)

Now of course come the serious testing for accuracy over distance but from this mornings results am optimistic about the prospects. It's pretty amazing to me that this project has been so sucessful to date, but the wealth of knowledge, experience and quality of guys on this forum is also amazing. Thanks to ALL for your imput and keep your fingers crossed for the accuracy tests!

[Hogtamer]

Not apples to apples I know, but for the heck of it plugged up holes in cooler, refilled, and shot a 130 gr Sierra Game King bullet out of my .270 motoring @ 3030 fps at the same cooler from 25 yds. It went about 1/2 way through the water. Nice mushrooming on this little fellow though and retained 58% of it's weight. Zlug, 100% retention and can shoot again!
142656

[Blood Trail]

HT, what do you plan on hunting these with?

[bikerbeans]

HT,

Good news and big fun to boot! I am hoping to get my friend's USH this week so I can test some more ZLUGS. Did you take the fish out of the cooler before testing?:shock:

BB

[Cap'n Morgan]

Now that's some serious zlug at work there! With that size, weight & speed who cares about expansion! I will not be at all surprised if accuracy is even better than factory slugs.

Fresh back from the range shooting 500 grains slugs @ 1400 fps from an eight lbs gun, I can't help thinking you're in for a convincing recoil experience once you abandon the lead-sled :shock:

[longbow]

Yahoo!!!!!!!! Indeed! Great work and great results!

Now if these were wad zlugs you certainly would be able to shoot them again! No engraving on the zlug to worry about, just reload in another wad and have at 'er again. You will probably get better and easier accuracy with full bore zlugs though.

So once you do some accuracy testing (which should go well) when do you plan to pop a hog?

Longbow

[cpileri]

great news Hogtamer!
now that the rains have come to Texas, hogs should be moving again; so might have some application!

[Hogtamer]

It's so stinkin hot or I would have shot some more today. Must be something to this global warming.....99* is a lot hotter than it was 30 yrs ago! Will try to get some shooting done within a week....work calls. IF these things turn out to be accurate there are some Savannah River swamp hogs in great peril over the next couple of months.

[Blood Trail]

I was hoghunting in east Texas last week by the Sabine River. Water was still way too high. Looked like the Mississippi.

[Electric88]

I'm very new to shotgun loading, and am curious about engraving. I keep hearing it mentioned, and don't understand the purpose of it. How and why would you engrave the zlug?

[William Yanda]

88
As I understand it, engraving occurs when the slug is marked by the rifleing of the barrel. The barrel is rifled to induce spin, to improve accuracy. Since the slug is larger than the diameter across the barrel inside the lands, there will be an impression of the lands on the slug. Engraving on this forum has a slightly more specific meaning than when used by a jeweler or machinist.

[cpileri]

HT, need to try those things in wetpack!

[Hogtamer]

I'll be happy to send a few to someone to document, but danged if I'm gonna accumulate and haul around wet newspapers! And clean it up? Are you volunteering Carl????

[bikerbeans]

Carl,

I would like to see a ZLUG tested in the cranium of a large feral swine.

BB

[Blammer]

I'd shoot that first slug again a few times to see how it does. :)

20ga testing should be next. :)

[longbow]

Okay, not finished yet but making progress when I can find time.

I had hoped to be further along but I am teaching a friend how to make a wood bow currently. Also, my kids are coming home to visit tomorrow for a few days so time is limited.

Anyway, here it is so far:

142856

The wad is machined from 1" thick polyethylene. A little long yet I suspect so I will have to play with balance point and hull volume (maybe 3" hulls for these?). Once that is sorted out, I will trim to length, load and shoot! I have enough polyethylene for at least a half dozen test zlugs.

I aim to do the zlug testing justice in a smoothbore.

Longbow

[bikerbeans]

LB,

Nice looking Zrenneke slug!

BB

[Hogtamer]

Didn't have to go to work till noon so dashed out and shot some at a piece of land where I hunt. Got everything together and got there with nothing to sit on, so shooting off table but on my knees, pretty wobbly. 1st 5 shots with zlugs @ 50 yds w/42 grns Steel...
Not bad but would have been better if I had just shot over hood of truck. The recoil on this load is about what I want....stout but very manageable, and that was the purpose of this project, a full bore slug with less recoil than the 7-800 grn bruisers. Shot @ 100 yds without scope adjustment and 1st 3 shots were off paper low. Moved elevation up and left (I thought, actually moved right and that is the far right hole I xxx out. So here are the next 8 shots...a little surprised that much drop @ 100 vs 50yds. Best guess 1600 fps +\- Overall very pleased but plan more testing. Off to work now.

[bikerbeans]

HT,

Progress, I like it! My friend's 12ga USH will be in my hands tomorrow so I plan to make a Zlug range trip on Monday.

BB

[Hogtamer]

Bet your groups will be better....this is an 870 which wins no awards for tight fit.

[bikerbeans]

HT,

I have the USH in my hands and will mount a scope tomorrow. Zlug range trip Monday if the weather cooperates.

BB

[bikerbeans]

HT,

I think you lost the bet.

Top target, 100 yards, 60g 4759, 6 shots

Middle target, 62 yards, 35g blue dot, 4 shots

Bottom target, 62 yards, 60g 4759, 5 shots.

All 3 targets are rotated 90 degrees, cameras hate me.

Blue Dot load is 1300 fps and the 4759 load 1370 fps, 10 ft from muzzle. I think I need to bump up the velocity and try again. Lots of residue in the barrel with the 4759. Recoil in the 12ga USH is mild.

BB

[bikerbeans]

Two Zlugs recovered from a wet clay berm behind the 100 yard target. I might found more Zlugs but the mosquitos drove me away.

BB

[Hogtamer]

I just got back from shooting myself, did a little better than that for whatever reason. Looking at Tom Armbruster's ballistic test, the 40 grn steel load velocity @ 4' average is 1525 fps with only pressure of 7800 psi. So I loaded 42 grs and should be around 1600 with still modest pressure. barrel nice and clean although he said lower charges were also dirty so a little extra pressure helps that apparently. My 34 grn Steel load that he tested was average 1371 fps and only 6433psi, definitely incomplete burn. My recoil is moderate and I'm gonna load a few with 44 grns and test again. Trying to make out from your pic, bit the zlug seems more swaged than engraved. How's the fit in that barrel? BTW I was shooting today with a little wind, 2 to 3 oclock 10-12 mph with gusts to 17. At 50 yds had a solid 2 1/2" group and 100 things opened up some. A couple center punched but several as much as 4 - 6" left. Does the wind effect those big old zlugs that much? Also, 90* which way? if holes are low wondering if crimp was consistent as that makes a huge pressure difference in a roll crimp. Another thing I learned from pressure tests, my roll crimping stunk as to consistency as I didn't have stop guage. Doing better now. Thanks for your efforts! Cpileri is gonna shoot a few as well so we ought to get a pretty good picture of these before we're through.

[bikerbeans]

HT,

Rotate the target pics 90 degrees clockwise.

My roll crimps are fairly consistent, I use a drill press with a depth control. I think the pressures are very low and the burn inconsistent. I plan to head out again later this week with some hotter loads. I may have to call Grafs and order some more Zlugs.:bigsmyl2:

BB

[bikerbeans]

I measured the 3 fired Zlugs I recovered and found them to still be round and very close to unfired diameter. I weighed them after cleaning with a small wire brush and,

466.7g
466.9g
467.2g

I can only dream that the slugs I cast would have this small a weight difference. I loaded these "recycled" Zlugs over 40g of blue dot and will test them shortly.

BB

[Hogtamer]

"Grafs" is ordering some more Zamak now! Just loaded some with 44 grs Steel but don't know if I will get to shoot this week. Oh and am reloading the fired hulls, no damage to them. Didn't expect to be able to do that with home rolled crimps.

[Hogtamer]

Got off early and headed to range with the 44 grns Steel loads. 20 shots, minute of torso:cry: Pretty stout but manageable recoil. And as usual seems like something other than loads going on. First shot good, 2" left of center dot. Next 2"low, 2" left. Next 2" . Then things began spreading out even though I allowed barrel to cool some. Shots started climbing the ladder, 3", 6", 10"..... so far this is a good 50 yd slug. i was so worried about the pressure initially, mow I wish I could add a coupla thou diameter to those zlugs.

[longbow]

I am turning the wads tonight and also miked the zlugs you sent. I get a pretty consistent 0.726"/0.727" which is a bit small for my smoothbore. I may try patching with one wrap of paper which works well for fit to bore but I am not sure it will survive opening crimp and jumping through the forcing cone.

I may try knurling first to see if that brings diameter up enough. If so they will all get knurled. If not then patching it is. In fact I may turn a few thou off the OD so I can use Teflon wrap which should take the abuse of opening the crimp.

I have to say that I have never spent so much time and effort making slugs but since you sent these for testing they will get made and loaded with respect so I get the best results I can. Problem is if they shoot well then do I have to do this for all my slugs/zlugs...!?!

Longbow

[cpileri]

The USH I plan to use has bore measurements of .721" lands, and .731" grooves. So we'll see. Might have to paper patch as well.
C-

[Hogtamer]

LB, a good excuse to finish that rifled choke project!

[longbow]

Hahahaha! I was looking at the started parts last night whilst tap drilling holes in zlugs so I can install 1/4 - 20 brass screws to hold wads to zlugs.

I decided to cut the polyethylene cylinders in half so I have 12. They almost seem a bit short but it all seems to fit and the zlugs are quite long so we will see. I may get zlugs tapped tonight. Normally I would use a wood screw but zinc is pretty hard so decided I would tap them and use brass machine screws.

I will try knurling a zlug later to bump diameter up to bore size.

I just came in from a day outside painting our beat up old trailer. HOT! HOT! HOT! It is 92 degrees in the shade on our back porch right now and I was in the sun. HOT! I am drinking a golden beverage (or maybe two or three) to cool down and rehydrate.

Yeah, I am slow but I'll get there eventually. Referring to both trailer and zlugs... and rifled choke tube and....

Longbow

[bikerbeans]

Pic is rotated again, up is left in the pic. The black target is 6 inches in diameter and I marked the 5 zlug impacts with orange stick on target repairs. I didn't measure but it looks like a 5-shot, 5" group at 100 yards. I used 40 grains of blue dot and I chronied the 3 previously fired Zlugs at 1502/1465/1463 fps. Recoil was moderate, hulls looked fine and ejected normally. I do agree with my chrony that I am getting a bit of velocity deviation, the recoil of some of the un-chronographed loads felt a bit different. Also there is still a fair bit of residue in the barrel so I am thinking of bumping the powder up once I get my next shipment of zlugs from "Grafs".

BB

[Hogtamer]

Looks like progress! Especially if you can shoot the same bullet twice!

[Hogtamer]

Sweet dream or nightmare? I have no idea about proportions but I'm willing to bet the general concept would excel.
10-12% f.o.c.

[bikerbeans]

Sweet dream or nightmare? I have no idea about proportions but I'm willing to bet the general concept would excel.
10-12% f.o.c.

HT,

If you make the nose flat (like a Buckhammer slug) you could load it pointy end forward for rifled barrels and flat end forward for smoothbores. I think you would need to keep the velocity below 1300 fps or get a very heavy slug gun. If you want to get a"feel" for the recoil of your design I have some 750g HB. fullbore (.732") slugs I can send you. These HB slugs are cast from WWs.

BB

[bikerbeans]

LB,

If you end up knurling a Zlug let me know how you do it. I have only knurled soft lead bullets for muzzleloaders but I don't think a file and a table top will do much to Zlug.

BB

[cpileri]

Hogtamer, are you going to make that doubel taper slug out of lead or zinc?

And yes, make the rounded end a flat nose or truncated cone!

[cpileri]

Guys,
Any luck w the knurling to bump up the dimaeter of these?
My grooves are .731" and i would like to test for accuracy so bore fit needs to be correct: paperpatching might throw off the pressure numbers.
I doubt it will be over-spec, but just want to be careful.
C-

[cpileri]

the rain has brought some pigs back, but lacking those: I can put a cow femur (fresh or dry) into wetpack to test for shattering.

[longbow]

Carl:

I haven't been making much headway lately... too many things on the "To Do" list.

When I read your post on knurling I decided I had better do something so I ran down the basement, looked out my knurler and gave it a go.

I managed to bump up diameter pretty easily to 0.730"/0.732". Not dead even diameter even though the zlug was a very consistent 0.727".

Now, having said that, my "knurling" wheel was machined down to remove the peaks and just be a textured driving wheel. The intent was to put "microgrooves" into a smooth boolit. I started out with a knurler similar to but larger (and cruder) than the Corbin unit with two smooth rollers and one grooved driving roller. it worked not bad but occasionally would slip which ruined a boolit. I tried a variety of options including regular knurling but opted for a textured driving roller, a smooth roller and a grooved roller so that I get several small annular rings (grooves) around the boolit for tumble lubing.

So, after that explanation, the point is that even with relatively flat topped diamond pattern on the driving wheel I still managed to bump diameter up by about 0.003". If I replace the driving roller with a deeply knurled roller and use two other knurled or maybe smooth idler rollers then I am sure it would bump diameter up more.

The Corbin knurler uses all rollers knurled but I didn't get good results that way when I tried because the pattern didn't match ~ I have two small diameter idlers and one large diameter driving roller.

Here is the corbin knurler just in case you are not familiar with it:

http://www.corbins.com/hct-2.htm

There are also a couple of threads on Cast Boolits with home made knurler designs.

Anyway, the short answer is that diameter can be bumped up at least 0.003" and I am betting more with full depth knurling on the roller.

Longbow

[cpileri]

I've used a file to knurl by hand lead slugs, but never a knurling machine.

I'll try it, as i only need to get to .731

Or else, I'll patch up.

I probably will try them as-is, too.

C-

[Hogtamer]

Would the raised surface of the knurl hold up to rifling - take spin as well as the undisturbed bearing surface? Can Tom enlarge the mold by as little as .002 with precision or is that too fine to expect?

[longbow]

Without knowing the bore diameter of Carl's gun it is hard to say. If rifling is shallow there may not be enough "meat" at the top of the tumble lube grooves for the knurl to hold up but if the bore diameter is at least a couple thou smaller than the zlug at 0.727" it should be okay.

If the rifling is deep ~ say 0.004" or 0.005" then Carl may not even need a knurled zlug to work. That hard zinc may just center up and shoot fine. After all, it is not sealing against gas as a boolit would be, the gas seal is taking care of that.

As for enlarging the mould by 0.002" a little lapping will do that pretty easily if you are careful. I would try them as is first. Second, I would try a hammer sizing die to knock them down a couple of thou then patch up and try that.

And another thought... powder coat. You can easily raise diameter by a couple though using powder coat if they don't shoot well naked. The zlug would still have to be larger than bore diameter so the lands bite zinc but the powder coat would help fill to the groove diameter for more positive centering in the bore.

I can knurl some and send them to Carl too. I'll have to make a new knurling roller or re-knurl the current one to get points back and get rid of the grooving roller. That should allow knurling up at least 0.003". I actually knurled some Federal jacketed factory .303 bullets up because they shot so poorly from my .303. A pulled bullet showed 0.312" diameter so I pulled several and then knurled jacketed bullets up by 0.003" and they shot quite well after.

Point being that with pointy knurl the surface of even copper can be raised quite a bit.

Anyway, let me know if you want some knurled for testing.

Longbow

[bikerbeans]

I like the PC idea. I may have a friend PC some of them and give them a try.

BB

[cpileri]

My grooves are pretty deep: gun is .721/.731, so grooves are .005 deep.
i will test all as you suggest.
C-

[Hogtamer]

Let me explain this pic. 100 yds w/35 gr 800X. The first shot is low left nearest the bull. 2nd shot is same height, further left. 3rd shot is off paper in the tape, same windage. Now this is the 3rd time this has happened, 2 shot ok then way high. Set amother target and shot .270 @ 300 yds, so took about 30 minutes and came back to Zlugs. 1st shot one of the 3 on left, so took average and adjusted windage right. 2nd shot is 3" below bull, had I not adjusted windage would be a nice group. 3rd shot 12" high above bull in wood. So this phenomenom has occured 3 trips. For reasons I can't begin to explain, 3 shots in succession yields 2 good and one waaay high. I mentioned this to Carl last week in a pm. maybe someone can explain. Does the same thing with the Steel load. Windage is not effected with the 800X load, more pronounced witht Steel. Obviously something to do with a hot barrel, as this 20" Hastings is pretty thin. Confident I could go back and shoot within a couple of inches
of the hole under the bull for 2 shots so it seems I've got a pretty good load here. Any thoughts as to why they climb the ladder consistently?

[Cap'n Morgan]

My best guess is that the barrel heats up unevenly due to part of the barrel being shielded/isolated by the forend stock. This causes the front of the barrel to rise slightly. Or it could just be residual stress from the machining of the barrel. I've had the same thing happen when shooting slugs from the bottom barrel of an o/u.

[bikerbeans]

Second box of zlugs arrived today. I loaded them in 3" bpi hulls with 70 and 80 grains of SR 4759. I am hoping getting the velocity up and the zlug closer to the forcing cone will help accuracy. Since HT appears to have a barrel heating problem I plan to wait 5 minutes between shots and go early in the morning when it is about 60F.

I talked a friend into powder coating some zlugs. I have to mail them to him so probably a couple of weeks before I can test them.

I spent some time thinking about how to load the six wheel weight zlugs I received. 1 3/4 oz. 12ga slug is probably gonna leave a mark!

BB

[Hogtamer]

BB, I think the barrel deal is specific to my gun. I remember same sort of thing with sabot loads last year and the thin remington barrel. A couple of decent shots then all over the place. Was blaming it on the scope. Funny thing, I had an old full choke barrel that I sawed off years ago and it was so much thicker steel, makes these new ones feel like tissue paper. And this was a 90/90 day here too...90* and 90% humidity. Man I'd love to breathe some 60* air about now. Those WW slugs are the first I cast with that mold, just to get a feel for it. Don't have to worry about them filling the bore...You could get your wife to shoot 'em cause I'm sure not! :veryconfu

[longbow]

Carl:

With 0.721" bore diameter I have to think there will be plenty of "bite" for rifling on the bearing bands. Rifling twist is relatively slow.

I'd try a few to see how it goes. If they do not shoot well then I can knurl some and send them to you if you want.

I am thinking that paper patching would not work well with such a hard zlug. if they were smaller diameter so under bore diameter Teflon wrap or possibly a tough paper would survive but as is I have to think that paper would just shear and fail. Mind you, with thin tough tracing paper it may shear and fail at the lands but if it fills the grooves it may do okay. Again, the zlug is not sealing against gas (except for leakage) so basically filling the bore and centering the zlug is the goal. Again, it is worth a try with a few.

Looks like I will finally make it to the range this weekend so I will have my Brenneke zlugs ready to go for testing. About time!

Longbow

[bikerbeans]

Zlugs ain't my accuracy problem!

BB

[cpileri]

My barrel is a bull, so maybe it will help tighten up groups if heating is the problem.

Looks like a bunch of blown wads there, did less-than-80gr 4759 do that? or just the 80gr charge?

[Hogtamer]

BB, camera still hates you! What am I looking at? Did those used to be gas seals? Maybe the Blue Dot is a better choice? Mine look like I could use 'em again.

[bikerbeans]

The 70g charge of 4759 also trashed the wads. I am going to order some new 3" hulls and decide what wads to use in place of the x12x gas seals.

BB

[elvas]

bikerbeans,
Find some tight hull fitted shot wads, cut the overpowder part of the wad and use it in place of the x12x or any other factory gas seal (they simply do not work because of faulty design). Adjust the free hull place using hard (nitro) cards and felt wads.

[longbow]

BB:

What are you doing using jellyfish under zlugs? Wait, those used to be gas seals!?! Well, they look like jellyfish (or at least the remains of jellyfish) now anyway.

I've had some bad blowouts but nothing that looks quite like that. it looks like gas was blowing by and stripping plastic along with it.

Longbow

[Hogtamer]

BB,
I have 000 experience with that powder but lots with x12x seals. I've loaded some Bazooka loads and never had a failure like that. Almost like they were canted over the powder - or something. Anyway, it just don't add up I tell ya!

[bikerbeans]

It looks like the x12x gas seals are a bit too small in diameter for the bpi hull. I have used their x10x seals over 95g of 4759 with a 740 HB slug without this problem but I was using federal hulls. I will go though my collection of wads and hulls and try to find a tighter fitting combo.

While I am waiting to get the Zlugs powder coated I will try the 770g WW-Zlugs. I also have a bunch of 730 grain HB slugs so i better call blue cross and get pre-approved for rotator cuff surgery.

BB

[cpileri]

It could be a sign of too high muzzle pressure, gas blowing them as they escape the bore and shredding them.

i had that when i was working on my 20ga Tri-ball loads, and RMc said that they had a similar problem unless they reduced the powder charge by a grain or so (of Blue Dot, not 4759) or else used a barrel 24" long (as opposed to 20"); both reduced the muzzle pressure to the point where the seals didnt fail.

[Hogtamer]

Isn't that what Greg warned about with slower powders?

[cpileri]

I got it from RMc, but i bet ya 3-and-a-half cents, give or take a nickle, Greg knows it too.

[longbow]

Well, I guess I missed that one! Generally I have not had the problem using Blue Dot or SR4756. The only time I have shredded plastic like that was when I decided to use up some old shotcups I had cut the gas seals off for wad slugs using nitro card wads over the powder. Yikes! There is a lot of gas leakage past nitro card wads let me tell you... cut those shotcups up badly.

I never thought about high muzzle pressure as being a problem but then I have not had many gas seals blow out badly except Win AA Reds.

I will use good gas seals under the Brenneke zlugs which hopefully will be shot this weekend.

Longbow

[Blood Trail]

I had some PT1205 wads look like that the other day when shooting Lee 1 oz slugs over 49 grains of BlueDot. http://images.tapatalk-cdn.com/15/07/09/4aaaef94c12a12279e8dbc87dcaad95a.jpg

http://images.tapatalk-cdn.com/15/07/09/481b7c7836b16b0488757a16a2d69a93.jpg

[Blood Trail]

Are those signs of over pressure?

[Blood Trail]

It could be a sign of too high muzzle pressure, gas blowing them as they escape the bore and shredding them.

i had that when i was working on my 20ga Tri-ball loads, and RMc said that they had a similar problem unless they reduced the powder charge by a grain or so (of Blue Dot, not 4759) or else used a barrel 24" long (as opposed to 20"); both reduced the muzzle pressure to the point where the seals didnt fail.

How did ur Tri Ball loads turn out? I'm messing around with them now.

[Hogtamer]

That seems like a huge load of powder to move 1 oz. Looks like the wads think so too. Any trouble ejecting hulls? Is the brass marked hard by the extractor? Any sign of leakage around primer? If yes to any come off that charge.

[Greg5278]

What kind of Hard Cards are You Guys using between the Zlug and the Seal?
Good Cards make a great deal of Difference. BPI has some Waxed Cards that hold up under Pressure.
Circle Fly has some 1/4" Cards that do well, but shred upon leaving the Barrel. Your Probably getting some Blowby in the Hull, because the Walls are so Thin on some Brands. You could proably even use a Waxed Card in place of the GS. X12X are great Seals. The OB12 can also work, but it depends on the Hull. If cost isn't an Issue the Ferderal .090" Hulls are the best on the Market. They also have the most internal Capacity on any currently available Hull.
Greg
AKA 12 Bore

[cpileri]

Yeah, 49gr is a lot of blue dot to move 1oz. what load data did you base that on?

Anyway, in the pic of three wads: the one on the left seems to have the skirt mangled, which could be a sign of gas blowby. It could also be mangled by a rough bore or by hitting something on the ground. the other two have skirts that are OK, but the rest of the wad is pretty well banged up.

The 20ga tri-bal turned out pretty well: 20gr Steel in PT wads, group nicely, still have to test them for penetration; which I plan to do when I test the zlugs. I am saving newspaper to make wetpack now.
http://castboolits.gunloads.com/showthread.php?250136-back-to-old-interests-20-ga-Tri-ball!
C-

[FullTang]

49 gr of Blue Dot is the max charge for 1 oz Lee slugs in the data provided with the mold, but it's for WAA12 wads. PT wads have a much bigger and more efficient gas seal, so these are almost certainly over 1800 fps. I don't know all the details of this load, but it's probably OK pressure with Blue Dot, just more than the wad can handle, since it's designed to handle 1 oz at 1300 fps.

[cpileri]

If its a max load w 1oz slugs, I'd back off: worried abt the pressure. Changing wads can change the pressure, and you do have evidence that its high. It MIGHT be the same and might even be lower, but why chance it? that might help your wad mangling problems too.

[Blood Trail]

I got the load data from Lee slugs except I substitute WAA12 for PT1205. I have no other signs of pressure. http://images.tapatalk-cdn.com/15/07/09/db30d982f63d75cbd8447065687c0abd.jpg

[Blood Trail]

I'll drop the charge on the next batch. Thanks guys!

And can someone explain to me why shooting shot has more pressure than shooting slugs of the same weight?

[Michael J. Spangler]

My friend came to the range last night with double lee slugs loaded back to back in a 12 gauge hull.
They were interesting to shoot for sure. Not to mention they looked like you could have loaded them again after we dug them out of the berm. cool stuff

wait now that i think about it i might have had that wrong. i think he had double lead slugs in the 10 gauge and the single slugs in the 12. either way pretty impressive.

[FullTang]

I'll drop the charge on the next batch. Thanks guys!

And can someone explain to me why shooting shot has more pressure than shooting slugs of the same weight?
Because shot acts like a liquid on "setback" and squeezes outward, increasing sidewall pressure and friction. A slug is solid and doesn't apply much pressure or friction on the barrel. There is some obturation of the soft lead, but it's minimal compared to the effect of shot. Things work very differently at 10-15,000 G's.

[longbow]

Shot "flows" and creates more bore friction that slugs.

[Greg5278]

I'd say Pressure is also part of the Problem with Your Wads. What size is the Overbored Rifled Barrel, Groove Diameter? I have a Mold for a .738" Diameter Slug that might work for You. You can also try a 1/4" Cork under the GS to prevent Powder Migration.
Greg
AKA 12 Bore

[cpileri]

ANother trick for powder migration prevention that Ajay used was a piece of newspaper: he cut a 1" square for 12ga, i used a 1" diameter circle.
Put that over the hull mouth after you charge w powder. use the gas seal to push the newspaper (only 1- sheet thickness) down over the powder, carefully so as not to rip the newspaper. Then seat your other components as desired.

[Firebricker]

Is the zamek you guys are talking about the same alloy as the old Atlas lathe gears? FB

[Hogtamer]

Zamak 3 is what I'm using, 96% zinc, 4% tin. There are several different Zamak alloys for different applications.

[bikerbeans]

I loaded a few zlugs over 45.4 grains of Blue Dot, (3) .125" nitro cards and a W-W gas seal that was designed for use in a compression formed hull. I used A-A compression formed hulls and Fed 209A primers. BPI roll crimper with a drill press. Two shots through the chrony at 1669 and 1655 fps.

I then tried to shoot a 100 yard group, first and second shot about 2" apart but the 3rd shot was 6" high. Loaded a 4th round and felt something move, stock had loosened up a bit. I didn't have my long 3/8" extension so done for day with the USH.

Prior to shooting the Zlugs I shot a few 730 grain HB slugs and one 770 grain WW-ZLUG. I think these heavy slugs are the prime suspects in loosening up the USH stock.

730g HB over 70g 4759 @ 1429 fps
730g HB over 75g 4759 @ 1582 fps

770g WW-ZLUG over 70g 4759 @ 1482 fps

Next trip will test PC Zlugs with Blue Dot and the W-W gas seals.

BB

[Hogtamer]

That blue dot load sounds really good....2 on and then high?....sounds familiar! 1600+ fps is motoring too. After all that, need ice? I lapped my mold some according to what was recommended here and may have added as much as .002' but I'm measuring with a caliper so we'll see. I'll shoot tomorrow and I hope to take up where I left off - taking ice water and towels to cool barrel though and see if that's actually a problem. Thanks for working on this BB! Soon it seems we'll be able to declare success that we can recommend without reservation or call it just another case of wishful thinking.

[longbow]

Well as usual I am slow. However, I do have all 12 Brenneke zlugs assembled. Ten out of twelve turn very true in the lathe and 2 have very slight wobbles (maybe a few thou).

Polyethylene wads are held to the zlugs using hex head capscrews (no round head 1/4 - 20 screws available locally) in counterbored holes so heads are flush with the base of the wad. Unfortunately since I am working in "spurts" when I get time, I wound up forgetting that I was supposed to knurl the zlugs before assembly. Since I used a glue "filler" to ensure everything lined up and set that way, I will not be disassembling to knurl. I tried paper patching with 2 wraps of parchment paper and they are a perfect fit to bore so that is the route I will go.

I'll post some photos of Brenneke zlugs later both wrapped and unwrapped.

Now to get to the range! I was supposed to be going today but not only am I not quite finished with zlugs, my shooting partner didn't call so the trip is off for today (that and I have another function to attend at noon). In any case, zlugs should be finished and loaded in a day or two so ready to go.

Hopefully testing will occur later this week or next weekend.

Longbow

[cpileri]

OK, I got them all loaded up fo the test. I chose the 40gr Steel powder charge for all in 2.75", 3" and 3.5" hulls; only difference was the
fiber filler wads used to make up the hull length difference.

I have factory rem 148gr 38spl wad cutter and a 4" bbl revolver to calibrate the wetpack, per this method:
http://www.frfrogspad.com/wetpak.htm

I am just saving newspaper now. I figure I will soak 48". If I get enough, I will make a wetpack w a cow femur or similar stuck into the wetpack which will be 4" wet paper, bone, then 44" wet paper. But i'll be carrying all that junk to the range myself and it gets heavy. So we'll see.


Someday soon.
C-

[longbow]

Progress! Slow but progress.

Slugs Undressed and dressed:

144395

So far "all dressed up and nowhere to go!" We'll get there though.

I patched with two wraps of parchment paper with a dab of glue at the bottom edge then rolled over the leading edge with the hope of it making it past the crimp. I also put 4 slits in each patch from about 1/4 the way up from the wad to the leading edge.

Now to decide on a load...

Longbow

[Hogtamer]

The 40 grn might be a little wimpy and dirty in the longer hulls.

[cpileri]

Yeah. I was thinking of accuracy though, since my chamber is 3.5".

If I had to do "it" over, i would get a rifled chamber cut, w no forcing cone, in a dedicated slug gun.

Anyway, I'm looking foward to the testing.

[Hogtamer]

Carl, I am too! And here's my morning range report: 15 shots @ 104 yds. 3" Win hull, don't know if the Primers in these new hulls I got a deal on are regular or Magnum 209 primers; 34.5 grns 800X and stiff wad column. This target is 17" diameter. Moderate recoil, not a mark on the hulls. 1st shot 10 ring. 2nd shot 9 ring. 3rd shot 8" high. Cooled barrel with cold wet towel. 1st shot 10 ring. 2nd shot 9 ring. 3rd shot 13" high. (marked those with orange sticker). This is the 4th time I have observed this phenomenon, that 3 shots in sucession the 3rd one is way high. So at least I proved to my satisfaction that's the way it is with this barrel. All the rest were 2 shots then cooled barrel w/cold wet towel and no more high flyers. Guess I can call this minute of deer shoulder @ 100 yds. I'd guess I could tighten group up by 1/3 if I were using crosshairs instead of 2nd ring down on this Nikon slug scope. zeroed @ 50 yds and 2 rings on this scope is 8" holdover from crosshair alignment. This ain't exactly tack driving I know, thinking about getting one of those H&R single shots w/heavy 24" barrel. Anybody got one of those to try? This may be as good as it gets with this gun.

[cpileri]

thats what mine is, a 24" bull barrel ush

[Hogtamer]

Alright Carl, show me something good and make me buy one!

[cpileri]

I can test them for acuracy kinda soon, but still need to create the wetpack to do penetration testing.

Off the cuff, i can say you wont regret buying the bull barrel USH- i love mine. Its weighted and has a nice pad so its not uncomfortable to shoot; it is heavy though. but I like it.

[Greg5278]

75 Grains of IMR 4759 anf a 730Gr slug is too Hot. If You're getting 1582 FPS it's way overpressure.
I'd have to dig through my Data to give a closer PSI Guess based on my Testing.
My Guess with the Shifting Warm Zero on the gun is a straightened and stressed barrel. It was probably drilled then Straightened, then turned for the Final OD. Just a Guess, but on a Cheaper Gun, probably a good one. Deep Hole Drilling a Barrel can be troublesome.
Greg
AKA 12 Bore

[Hogtamer]

Greg, Biker Beans is who shoots the 4759 and I'm the one shooting 43-44 grns Steel or 34-35 grns 800X. My barrel is a cantilevered 3" chamber Hastings 20" on an 870 Express and I'm getting the highballs.

[Greg5278]

Barrel Warping on a Hastings? Maybe They overheated the Barrel when Brazing the Cantilever.
I haven't tried a Cantilever setup on a Gun Yet. I normally shoot fully threaded Barrel Ithacas with the Scope D and T on the Receiver.

I was just mentioning the Load of 4759 was a bit Hot for Safety in some Guns. It should be fine in some, but like the .45 Long Colt not all Guns are in the same Class.

Greg
AKA 12 Bore

[bikerbeans]

Greg,

I agree the 75g load and 730g slug would be a bit much for some guns. My data "source" indicates this load is fine in the heavy barrel USH.

BB

[Hogtamer]

Sending another couple of loads to Ballistic Research to test: 1) 44 grns Steel, 2) 35 grns Hi-Skor 800X. I have shot both and they seem fine, just want to get everything squared away. Good advice from LB!

I've looked at most of the retailers and can't find an H&R USH anywhere. Just got the itch and already have a couple of scopes. Just too blaming hot to do much of anything but breathe here lately and for the rest of the week. Maybe shoot some more Monday. Hope to hear from the rest of you guys soon.

[cpileri]

looking foward to the results.

(and still collecting newsprint)

[Greg5278]

Try asking at the Recycling Location for Phone Books. They often have Stacks of Them hanging around.
Maybe the Post Office woulkd have a bunch after the Mailing goes out?
Greg
AKA 12 Bore

[cpileri]

If i remove the covers, would they be about equivalent to the wetpack i'm trying to replicate.

If I get enough, i was going to try one of your slugs/loads, greg, just to see if i can get 49 inches out fo it- as a comparison of course.
C-

[bikerbeans]

HT,

I hope to have my powder coated Zlugs next week and make a range trip. Going to stick with blue dot powder. I need to remember to save a few Zlugs to send in for pressure testing.

HT, any interest in a 10ga HB Zlug? I have a 10ga HB mold that casts WW + 2% tin at about 740g. I may order a few pounds of zamek alloy #3 and give it a try.

BB

[Hogtamer]

Don't own a 10 ga. BB but thanks for the offer. I'd hoped to have some pics of zlugs and pigs today but word must have gotten out that I was coming. Plenty of sign but no pigs.

[Hogtamer]

Checked with Tom Armbrust and he'd not received the last batch of zlugs. Turns out the girl in the office who printed the FedEx label for the first batch thought she'd just Mail these! Geez, if you guys don't hear from me in a couple of years I'm prolly in the Federal pen...

[longbow]

I'll bake you a sourdough chocolate cake with a hacksaw blade or two in it. We'll get you out!:smile: Besides which you haven't lived until you have had sourdough chocolate cake! So, win, win... sourdough chocolate cake and escape! What more can a guy ask for except beer when it is that hot.

I am still waiting to get range time. Got the slugs patched, weighed and ready to go. I will be using Blue Dot at about 35 grs. based on weight and possible bore friction for my Brenneke Zlugs. I have used 35 to 38 grs. of Blue Dot successfully for lead slugs from 1 oz. to 580 or so grs.

That was with up to 0.735" lead round balls and at 38 grs. of Blue Dot I had about enough recoil, though pressure "should" not have been high.

Based on weight alone I would go somewhat higher but I fear my Brenneke Zlugs may have significantly more bore friction than a bore size slug so I will play it safe.

Maybe this weekend!

Longbow

[bikerbeans]

HT,

How's prison life?:bigsmyl2:

Hope to shoot the PC Zlugs next week.

BB

[cpileri]

how much did the powdercoating increase the diameter?
That might be just what I am needing for a proper bore fit.
C-

[Hogtamer]

BB, those things are evil looking man! I like 'em. And neither the ATF or Postal Inspector came to my house....whew. In fact Tom called last night and said zlugs arrived via USPO. On MondayI went by the PO and told them what happened, that the package had the ORM-D markings on 3 sides of the box, etc. Told me it would prolly get there.....Huh? Ok, whatever as they say. Did take the better part of 2 weeks but will have more load info to pass along soon. And an USH to try them out of next week too.

[Hogtamer]

Wow, Double Wow! Tom got shells last night and shot them today and really good news...

5 shots.
3" Win Hull
Fed 209a primer
44 grn Alliant Steel*
1708 fps
10,600 pressure

*Said 1 more gr powder would be fine.
__________________________________________________ ________

5 shots
3" Win Hull
Primer***whatever came in hulls, 209 or 209M. Any way to tell? They do have a reddish tint newer win 209s don't have. these are all new hulls that I got a deal on.
35 grns Hi-Skor 800x
1608 fps
11,160 pressure

OK, now who on here has a sharp enough pencil to calculate ft/lb of energy the Steel load delivers assuming 467 grn Zlug????

[bikerbeans]

I only have a picture of the PC Zlugs so no measurements. Per USPS they should arrive on Saturday.

BB

[cpileri]

3026 ft-lbs energy

[cpileri]

bullet weight (in grains)
speed ( in feet per second )
Energy = Weight x Velocity x Velocity (yes, twice) divided by 450395

[Hogtamer]

Go to the head of the class Carl! Thanks,

[Hogtamer]

Carl, since your calculator is smokin' can you extrapolate the energy @ 100 yds? Bullet length = .79, weight 467 grns, dia. .728 looks like ballistic co-efficient ~ .2 best I can figure. I am assuming hot summer temps and high humidity = you have some time on your hands also! Also, if it takes a day and a half for a chicken and a half to lay an egg and a half, how long would it take for a bow-legged rooster to peck a hole through a pine 2x4?

[Greg5278]

Energy is Velocity in FPS Squared X Projectile Weight in Grains
Divided by 450,240

I doubt the BC fore the Zlug is going to be .20, probably more like .13-.15.
You would have to shoot it for Velocity at 2 different Ranges and Calculate the Velicty loss.
JBM Small Arms Ballistics can do it if You have the Chronograph Readings.
Greg
AKA 12 Bore

[bikerbeans]

http://www.jbmballistics.com/cgi-bin/jbmstab-5.1.cgi

BB

[cpileri]

OK, 467 x1708x1708 / 450240= 3025 fpe

still a really good whack


Energy is Velocity in FPS Squared X Projectile Weight in Grains
Divided by 450,240

I doubt the BC fore the Zlug is going to be .20, probably more like .13-.15.
You would have to shoot it for Velocity at 2 different Ranges and Calculate the Velicty loss.
JBM Small Arms Ballistics can do it if You have the Chronograph Readings.
Greg
AKA 12 Bore

[bikerbeans]

I think USPS may have lost my PC Zlugs.:evil: The package was an hour away 2 days ago and no updates since.

BB

[longbow]

I am still trying to get out to the range to test my Brenneke/Zrenneke... whatever zlugs. Unfortunately I blew a head gasket in my truck so now my Zlugs are all dressed up with no place to go... or at least no-one to take them until I get the truck fixed.

I am about to start disassembling the truck in my driveway. Fortunately it is a 1981 Chevy pickup with good old fashioned carburetor so not too bad. Yes this is my daily drive to work commuter. I do not much like fuel injection. Oddly I bought the truck with a recently professionally re-built engine in it (383 stroker). It should have lasted well but didn't. If you want something done right... well, you know.

I am still following the thread with interest and one day will contribute.

Longbow

[Hogtamer]

Dog Days.....on a brighter note, I got my 3 shotguns yesterday that I bought off Gbroker. The Browning 2000 I can't believe. Couldn't have been more than a box of shells run through this thing. Of course the guy that bought it hadn't bothered to clean the packing grease off in'79 when it was new, it prolly hung up a couple of times and in the closet it went. Disassembled and got the petrified oil off it and it looks and feels brand new. The old wingmaster is in better shape than both of mine I already owned, really nice old gun from '60s. Andthe H&R USH is just, well, ugly as the swamp rooters I hope to kill with it - in other words, PERFECT! Got it scoped up and will have a report maybe Sun. or Monday. Sorry about the ride LB, worse things to fix than head gaskets though.

[longbow]

Yeah. Got it down to the intake manifold after work. I wish I had a steam cleaner or power washer but... nope. I will do a good clean up before pulling the intake manifold.

Not the most hygienic place to work and not the cleanest engine to disassemble but the heads will be solvent cleaned and block all wiped down as best as possible.

Could be worse for sure but I think this may be my last set of head gaskets I replace. Been there too many times and I am getting to old for this. I want to be fishing and shooting and flinging arrows, not under the hood of yet another old vehicle.

At least the old Chevy's are cheap to fix. I look at headsets and laugh at how cheap they are. My wife's Mazda MPV got 3 sets of head gaskets in it (long story and mostly due to poor shop/milling). Those head sets were $300.00 and you also had to buy new head bolts (torque to yield) at $180.00! OUCH!

All in all i would rather be shooting! That'll come though.

Looking forward to your report with the USH. I wish I had picked one of those up now. They will be getting hard to find and probably really hard to find in Canada. I doubt there were ever many here to begin with. Oh well.

Longbow

[bikerbeans]

The PC Zlugs have arrived! Measured just under .730" with a digital caliper, too lazy to look for a mic. I loaded 8 of them on top of 45 grains of blue dot and plan to hit the range first of next week.

BB

[Hogtamer]

Went out early this morning to put up a ladder stand where I saw a nice buck last year,,,,bow season starts next month! Humidity was oppressive and by the time I put it together, drug it 200 yds and got it up I was wasted. BUT, just had to shoot, first time with the zlugs and the USH I got scoped up. (took off of 870). Windage was fine but elevation off and worked through that, put up a new target @ 50 yds and by this time I'm shot, but here it is (the paper target) Put up a splatter target ranged at 101 yds. Used the 1st ring below crosshairs (Nikon slug scope). Planned to shoot 10 but cramps and heat made me quit. The first 3 in center looking good! Did recover one zlug and it had barely any rifling engraved, so thinking need to lap mold some. Whew, Did I say hot and humid??? Oh, these were the 800x loads @ 1600fps.
146904

[bikerbeans]

HT,

I tried the PC Zlugs over 45 grains of blue dot today in my friend's USH and not so good. 3 shot 6" group at 50 yards and 5 shot 10" group at 100 yards. The PC Zlugs are a good .004" under groove diameter so I am thinking your ideal to open up your mold should help. I have a handful of the PC Zlugs left so I will send them your way as it is time for me to return the USH. Sorry I wasn't abit more helpful.

BB

[longbow]

Maybe try paper patching those if they are still 0.004" under groove. Hard zinc might be tough on paper but the PC should give a bit. Uncoated zlugs should be about right for paper patching.

A good tough tracing paper should survive or something with high linen content. Regular printer paper doesn't have enough fiber I don't think.

It's worth a try anyway.

Longbow

[cpileri]

Hmmmm...bad news.
the slugs i loaded for the upcoming penetration test (still saving newspaper) are intended for use in a USH. The shots will be at close range, so it should still work.

But too bad on the accuracy.

[bikerbeans]

Hmmmm...bad news.
the slugs i loaded for the upcoming penetration test (still saving newspaper) are intended for use in a USH. The shots will be at close range, so it should still work.

But too bad on the accuracy.

C-,

Don't give up, might just be me or this shotgun that is the problem.

BB

[Whiterabbit]

HT,

I hope to have my powder coated Zlugs next week and make a range trip. Going to stick with blue dot powder. I need to remember to save a few Zlugs to send in for pressure testing.

HT, any interest in a 10ga HB Zlug? I have a 10ga HB mold that casts WW + 2% tin at about 740g. I may order a few pounds of zamek alloy #3 and give it a try.

BB

Hey Biker,

Do you think bluedot makes for a fine powder to use for 20ga slugs in brass shells? Just looking for backup powder ideas.

[Hogtamer]

Lapping the mold bit by bit, several thousands ought to do it. Carl, have you slugged that USH? I have not but clearly a little bigger than the Hastings barrel judging by rifling on fired Zlug. The gas seal has rifling marks from the Hastings but not from the USH.

[bikerbeans]

Hey Biker,

Do you think bluedot makes for a fine powder to use for 20ga slugs in brass shells? Just looking for backup powder ideas.

WR,

I have almost no experience loading all brass hulls with slugs. I had some new 20ga magtech brass hulls but the inside diameter was too large for my fullbore slugs or any of my bullet/wad combos. I sold the brass hulls before I tried to make a crimp die. Blue Dot works fine for me with fullbore 1oz slugs in brass/plastic hulls.

BB

[cpileri]

yes, slugged to .721 lands/.731grooves

[Hogtamer]

Ok, looks like I got it to .731. We'll see soon if that's the ticket or not.

[Hogtamer]

Well I cast with the lapped mold and loaded. Tightened up a bit but recovered zlugs revealed that I got the mold out of round a bit so that only 2 opposing lands engraved the boolit. Talked to Tom at Accurate and he is going to try to add .0045 from the original. Men, this thing is real close to being just right. Minute of hog shoulder @ 100 yds is where I am right now and that could be it, but we'll see. Taxing my ADD as bow season on the horizon though!!

[bikerbeans]

HT,

Thanks for reminding me about whitetail archery season and ADD! Opening day for me is the last Saturday of September and I haven't touched my bow since last november. I do cheat on archery by using a crossbow with 2x scope, some years I have to take 5 or 6 practice shots to get ready for hunting.:bigsmyl2:

BB

[Blood Trail]

Oh yes, archery season is upon us (almost anyway in Texas). Yesterday was opening day for dove. Limited out in no time. My little boy (7 years old) shot 6 and only ground swatted one!

But speaking of archery, can't wait to take these beauties out. http://images.tapatalk-cdn.com/15/09/02/cbc0d9158b8192d4be092ceff9a4628d.jpg

http://images.tapatalk-cdn.com/15/09/02/6c1e266562ecefc07fa1f08eed540326.jpg

http://images.tapatalk-cdn.com/15/09/02/d5065fa9c9ea5522f6f62b67a79bb785.jpg

[Hogtamer]

Beauties! Doves the weekend for me, deer season the 12th. Not much for deer hunting in the heat though. BTW, will have mold back from Tom this week and will see how the bigger zlug effects accuracy.

[longbow]

Wow! Nice arrows and knapped points there Blood Trail. Those look great. River cane shafts?

I'm guessing those are going hunting with you. Good luck.

Longbow

[Blood Trail]

Wow! Nice arrows and knapped points there Blood Trail. Those look great. River cane shafts?

I'm guessing those are going hunting with you. Good luck.

Longbow

Yessir. Rivercane.

[bikerbeans]

HT,

Given how hard the Zlugs are you might consider starting with a reduced powder charge. Maybe just try and tap the bigger diametet zlug down your barrel and see if it puts up more of a fight. Good luck with testing and your hunting.

BB

[longbow]

Do you do your own knapping? Very nice job!

[Hogtamer]

Got mold back from Tom yesterday and he did a wonderful job. Cast some lead to slug barrel. My USH measures .719 on the lands and .731 grooves. The Zlugs now measure .7305 to .731. (got a machinist buddy to measure all). 10/4 on the reduced load. Should be biting .006 per opposing side of the rifling; whadda ya think? This oughtta do the trick but won't know tomorrow cause I've got a dove date!

[bikerbeans]

Yessir. Rivercane.

You guys with talent make me jealous. I could never make an arrow from scratch. I consider myself lucky when I assemble a fixed blade broadhead and don't cut my finger half off.:-D

BB

[longbow]

I think you are going to be alright Hogtamer. That design doesn't have a large bearing surface and you are just at groove diameter. Nonetheless, starting with a lighter load is a good thing to do then work it back up.

Are you using a good plastic gas seal under the Zlug? If so have you recovered any? What do they look like after firing?

Have you recovered any fired Zlugs? I'd be curious to see the rifling to see if it is even all around the Zlug. If recovery is difficult due to penetration try several water jugs or a couple of buckets of water in line then a bucket full of rags to catch the Zlug.

Longbow

[Hogtamer]

the BPI x12x is a great gas seal and could use again. My last outing after lapping the mold showed only 2 lands engraving so I apparently got it out of round a bit. Tom fixed that though. Accuracy was not terrible but threw a couple of flyers. Minute of pig shoulder @ 100 yds but I'm looking for rifle accuracy which may be optimistic I know. This last machining should remove all but one variable, which is consistent roll crimping height and compression on hard card wad column. I'm using one 1/2" and one 3/8" premade wad but there is still a degree of "squishy" give....you through with your mechanic impersonations on your truck yet?

[longbow]

Hah! Nope! The truck saga is on going.

Long convoluted story so I won't bore you with all the details. Short version:

- blew a head gasket (new Chevy 383 stroker in a 1981 pickup... no, not restored, just in reasonable shape)
- I bought the truck from a guy who had the engine built to tow his 26" trailer so it should be good for my 18' trailer
- pulled the heads and found really thick head gaskets at 0.050" and flat top pistons at 0.025" deck height making for poor squish/quench
- my suspicion is that the shop that built it simply put thick head gaskets in to keep compression low enough for pump gas
- next I found a cracked head... Doh!
- the more I investigated the more I learned and it looks like these guys should have used dished pistons to get compression right, proper squish to get combustion right and normal thickness head gaskets
- since I am stuck with what I have I will be going thinner head gaskets to improve squish and hopefully still be able to run less than 94 octane gas (very expensive for 94 octane here)

If I had a nice big shop I would pull the engine, install dished pistons and put it all back together right but I am working in my driveway so head replacement is all it gets.

Not at all strangely is that bare heads in Canada cost twice as much as complete heads out if the States. I am trying to get sorted out to order a pair of heads from EngineQuest or BMP. I have to get them delivered to Washington State though as having them sent across the border becomes prohibitively expensive. I can drive them across.

Hmmmmm, that wasn't so short but not nearly as long as it could be. If I threw money at it and paid a mechanic to do the work it would a short story but that would be too much money for me to justify. Better to replace the truck which may yet happen.

Due to all this I have not been out shooting. I'll get there though. I've got a dozen Brenneke Zlugs all dressed up and ready to go along with a bunch of other slugs to test.

If I ever get this truck back together I might get back to the rifled choke tube project too.

Longbow