The ZLUG Thread

[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:



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.

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 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