New full bore slug

[hollow-point]

have you looked at cast bullet engineering 12g molds? he has a few designs and a paradox style H-P is one of them.

[megasupermagnum]

have you looked at cast bullet engineering 12g molds? he has a few designs and a paradox style H-P is one of them.

I had never heard of them before now. The one 730 grain mold looks about what I'm going for.

I am still waiting for the mold to be sent to Erik. I got my 5 cavity mold last week that I had ordered on the same day. I'm guessing it will still be another month or better before I get to cast the new slugs.

[MotelAlpha]

Looks okay to me though I think i'd go a hemispherical RNFP... but then I am thinking smoothbore. Things are a bit different for rifled gun.

As for the HB and skirt, I'm with BB on it likely being best to heat treat. I haven't run into a skirt yet that hasn't deformed some if not heat treated no matter how thick it was, and still looked like an HB slug anyway. I fill the cavities partly to support the skirt but mostly to keep wads out of the cavity. Heat treated or not if the slug has a hollow base wads will try to get in there, even nitro card wads. You could copy the Lee Drive Key or get a tapered hollow bored/reamed into the core pin like the Russian Paradox slugs so the skirt could be thinner but the wad would be stopped by the central pin.

I wouldn't go any thinner on the skirt than 0.100" ... at least without a pin or "key", but that's just me.

If you don't fill or use the key/pin idea then put a tough disk like polyethylene under the slug. That should keep wads out.

As for weight, you could lighten some by using just two driving bands and leave a wide, and deep as Tom can cut, groove. The old Paradox slugs had a huge groove! They were solid body so heavy even if they were HP'd but a hollow base design would lighten them a lot. I've always liked the Paradox design:

https://www.classicshooting.com/coll...ant=1179491392

I'd stay away from too large a flat on top of the pin. I made mine fairly flat so keep lead in the nose but if I don't tip the mould a bit while pouring I often get a little cavity at the top due to air trapped over that big flat. Bubbles seem to flow off a radius or point but seem to hang onto the flat... at least in my mould. I think your radius looks good.

That slug would probably shoot just fine as is from rifled gun.

Longbow

I had a Hollis 12ga SxS that was a Ball/Shot gun with very slight rifling that came cased and a slug mold exactly like that....it shot very well...680 grn slug 26 grns 4756.

[megasupermagnum]

I finally got the mold today, and couldn't be happier. Like anybody, I had the pot heating up before I even opened the box. I had the pot set at 750F, and it casts fantastic. I don't know why, but I always got well over half as rejects with the aluminum mold 73-770S. This new mold, once warm makes perfect slugs. They drop right off the pin no problem, and being as it is encased in a brass mold, it holds heat well. I only ran off a couple dozen, as the alloy was my mystery metal, just a mix of everything left over that I use for target ammo. It seems soft. I can't scratch my favorite 96/2/2 alloy with my finger nail, but I can with this metal. Weight comes out to be about 765 grains. They definitely have a weight forwardness, but I'm not sure if they will fly from a smooth bore. I will be sure to try though. The walls are thick, .150" at the base, so hopefully will resist hard cards trying to force into the cavity. The bearing surface is about .6", which should just barely bridge the forcing cone from hull to bore. The best I can measure, the forcing cone on my USH is about 1/2" long.

[bikerbeans]

Very nice! Now remove that HB pin and cast a real slug, probably 900 grains.

Hollow Points HB pin conversion is first rate.

BB

[Hogtamer]

That slug in 20 ga hb version is more my load these days. You guys are nuts, or soon will be shooting that monster! Those brass molds sure make pretty slugs, whatever size.

[megasupermagnum]

That slug in 20 ga hb version is more my load these days. You guys are nuts, or soon will be shooting that monster! Those brass molds sure make pretty slugs, whatever size.

The trick to heavy slugs, is a heavy gun. My USH is pushing 11 pounds. I agree, if I were to start completely over, I would have gone with 20 gauge. Estimated weight with a plain base is 943 grains with wheel weights. I want to try heat treating these, so it could be a few weeks before I try these out.

[megasupermagnum]

One thing I forgot to add is the two slugs I measured were .7358". I was hoping for .733", but that should fill the hull nicely.

[megasupermagnum]

I have been playing with these slugs for the past few weeks, with no luck. The three wad stacks I've used are x12x + (2) 1/4" felt wads+ (3) 1/8" nitro cards, the second is a x12x + (6) nitro cards, and the third x12x + 1/2" fiber + (3) nitro cards. I don't know why, but the felt wads cause terrible leading. Maybe they push up in the cavity of the slug? The best so far is the fiber wad. I've only used Blue dot powder so far. The slug is heat treated COWW, for a BHN 26, and one coat of Lee Alox. I may try pan lubing with a soft lube, but Alox seems to do the job well enough. Recovered wads look perfect, no indication of going into the hollow base. The problem is I can't get a decent group at all. After putting up a big sheet of paper, I found the slugs shoot high, but in a group 8"-12" at 50 yards. Usually things are going VERY wrong to get groups this big, yet the holes on paper are perfectly round. Absolutely no sign of wobbling or tumbling. It is worth noting that some other slugs I tried were not shooting very good, so it may be time to break out another slug gun just to rule out a problem with the ultra slug hunter. It was raining, and the berm at 100 yards was perfect for recovering bullets. I got a bunch in a good area, but only managed to recover one. I see no problems with it at all. The rifling looks clean, and centered, it is not engraving crooked. The hollow base looks perfect, no deformation at all. It is interesting that even heat treated, the nose got a big ding, probably from a rock. Even still, I just don't see how these slugs could be shooting as bad as they are. Maybe the big hollow base is just not conducive to good flight. I have been thinking of trying some as a solid slug, a full 940 grains. After casting them, I could flip them over and fill with lead. There would probably be more weight variation than the proper mold, but if my groups shrink down significantly, I know it's the balance.

Also, I ran some over the chronograph with 32 grains of Blue dot: 1050 fps

Attachment 225820Attachment 225821

[longbow]

Is that HB pin removable from the Cramer sliders? If so then a piece of round bar would likely replace it with minimal machining... or get Eric to send you a flat topped blank like Miha does. Then you can cast a real solid.

I'd try filling the cavity with hot melt glue before getting too carried away though.

If wads are pushing into the cavity they may be hanging on part way affecting flight or they may be distorting the base a bit... maybe not obvious but if the slug is say 0.002"/0.004" out of round you'd never see it but a 1:36" twist will make if wobble in flight.

I doubt filling with lead would work. First off the lead will not bond and it is a comical hole so the lead core would likely just fall out. Second, even if it stayed it would be difficult to cast a homogenous core of even weight so there again any off center void will affect flight.

I can't see any good reason that the slug wouldn't be shooting better than you are finding unless there is something "out of whack". Wads pushing into the base would be my first guess and filling the cavities with hot melt glue is easy and will stop that. If that doesn't improve groups then keep looking.

Also, I'd try a plastic gas seal then hard card wad column with nitro card on top. Felt and fiber are cushiony and may be crushing unevenly. Its another variable. I had terrible results with plastic wads and fiber wads under 0.735" RB's. Once I went to just plastic gas seal and all hard card wad column results were much better.

Its a good looking slug in a rifled barrel so I have to think you can get it to shoot.

Is it at least groove diameter? I've been assuming the slug fit is good and I'd figure at 0.735"+ it is filling the grooves.

MotelAlpha: Thanks for that info and load data. It may come in handy!

Longbow

[gpidaho]

You all know I'm pretty new to this but I wonder why you guys aren't powder coating your slugs if your getting leading? I've already tried it on round ball loads and it works just like it does on my rifle and pistol bullets, no leading. Gp

[megasupermagnum]

For the most part, leading is a non-issue. I even shot a different slug bare, as in no lube at all, and didn't see even the tiniest bit of leading until 50+ rounds. When leading is severe like I had in one case, something is very wrong. Once corrected, that slug shoots clean. Same with .735" round balls, it was not a problem for me. The velocities are so low, twists so slow, and wads to keep from any gas cutting, so there is no problem.

@longbow I did try an all nitro card stack, but it did not make a difference. I'll see about making a blank for the mold, the hollow base pin does look like it comes out.

[megasupermagnum]

Upon closer inspection, the base pin is actually held in by a roll pin, and it is not drilled all the way through. It looks a little small for me to want to try and force out. Maybe hot glue in the base is the best thing to start with, and see if it improves.

[Cap'n Morgan]

I have a hunch that maybe the muzzle blast is disturbing the slug when it leaves the muzzle. You could try using a faster powder or reducing the load to see if things improve.

[megasupermagnum]

I have a hunch that maybe the muzzle blast is disturbing the slug when it leaves the muzzle. You could try using a faster powder or reducing the load to see if things improve.

It's possible, but I'm not shooting these all that hard. I've kind of settled on 32 grains of blue dot for testing, and there is little muzzle blast. Very little flash either.

I just loaded some up with 30 grains, with an all hard card wad stack. I checked the gun over, couldn't find anything wrong. I will also try it without the fore end. I had cut grooves and filled with some lead, so who knows. Maybe something worked loose, and was causing weird pressure points on the barrel.

I'll also load some round ball with a load I know is accurate.

[longbow]

Have you checked slug weight for consistency?

I made a mould based on turbo1889's 10 ga. slug scaled to 12 ga. and I found that the near flat top on the HB pin would catch bubbles of air making for cavities on top or above the pin. Tilting the mould as I poured helped to minimize that.

Maybe you've got some cavities in the slugs?

Something has to be wrong if that slug doesn't shoot any better from a rifled barrel.

Yes, I'd try the hot melt glue. I fill my slug cavities to overflow then invert and press down on an oiled piece of steel to squeeze extra glue out and leave a flat base. Alternately you can over fill then use a utility knife to cut the excess to flat base. However you do it you want a nice flat base when your are done.

I have to think there is some issue to solve rather than the slug just won't shoot. Do you have another rifled gun to try it in?

Longbow

[longbow]

On second read. I note you are using 30 grs. of Blue Dot. Are you getting complete burning? I found that Blue Dot likes pressure or burn gets a bit erratic. Not sure just how much BD you should use with 765 gr. slug but if there is unburned powder in the bore you may need a bit more powder/pressure to get consistent burn.

[megasupermagnum]

On second read. I note you are using 30 grs. of Blue Dot. Are you getting complete burning? I found that Blue Dot likes pressure or burn gets a bit erratic. Not sure just how much BD you should use with 765 gr. slug but if there is unburned powder in the bore you may need a bit more powder/pressure to get consistent burn.

Absolutely, I will get these to shoot, I'm just reporting my observations good and bad. 30 grains is pretty mild, but the chronograph shows low velocity spreads. I just find 32 grains to kind of be the standard I use, no particular reason, but it performs well with a huge range of loads. When I figure out what is going on, I will go up in powder. Load data for 1 3/4 oz goes up as high as 40 grains, and 2 1/4 oz (in a 3 1/2" hull) shows a max about 38 grains. I've found Bluedot to work well over a huge range, but always seems to work better with a heavy payload. It seems to become much more consistent and predictable.

When shooting yesterday i had the perfect example. Those BPI value slugs, a 300 grain sabot, with 42 grains of bluedot throws a huge fireball, and is loud as can be. 32 grains behind a 765 grain slug was pleasant, no visible muzzle flash at all. A few weeks ago we had a problem with a fox eating chickens. One night before bed (maybe 1 am) I heard not one, but two calling very loudly outside. I had the shotgun, a 20" barrel mossberg 500 no less, and 32 grains of bluedot with 1 3/4 oz of #F. There was hardly any muzzle flash, and it was not even that loud either. I got one fox, never saw the other, but it never came back. I believe pressure helps it in cold weather, but I've had nothing but good results, even well below zero.

Yes I weighed all slugs, and hand sorted them with a careful eye. I too found a few with an air bubble on the flat top. These slugs are as best as I can produce, all weigh about plus or minus 2 grains. If my groups improve significantly with a filled base, I think that will tell me right there my problem. If not, I'll continue looking, one variable at a time. At this point I'm leaning more towards hunting with the .735" round ball. Those are good to at least 75 yards. This hollow base slug is just a project to see if I really can improve on the square shoulder slugs.

[longbow]

You'll get this beat. That is a good looking slug and no reason it shouldn't shoot well once you find what it and the gun like.

If velocity spread is low and consistent the powder must be burning well enough.

I like Blue Dot too. So far it is the best powder I've used for slugs at least with moderate to heavy loads. There are other powders I'd like to try but availability is an issue where I live... selection is poor.

At +/- 2 grains you've got no worries there either. I just figured I'd mention it just in case.

Filling the cavities is easy and if things improve it tells you something. If not well, there's got to be something happening that shouldn't be. Its all in the details.

Speaking of filling cavities... with that conical pin even hot melt glue may not stay in and it wouldn't do to have some plugs stay in and some not. I wonder if paraffin wax might be a better choice as it is likely to fall out.

This is when it would be nice to have slo-mo to check on these things in flight.

Keep at it and you'll win!

Longbow

[megasupermagnum]

I had been thinking about that, and I even tried filling a couple with lead. They fall right out. I have not tried hot glue yet, but I was thinking if I could just etch a few grooves inside, they would have something to hold onto. Maybe even just a couple turns on some sandpaper. I'll figure something out.