Boolit base deformation

[Hannibal]

I've been fooling around with a Henry .357 trying to get it to shoot cast. And while I am having success with a couple of other boolits, Lee 358-158-SWCs have been a colossal failure. At first I surmised this was because the lack of a throat on the Henry was causing nose deformation, but I've built a bullet trap and discovered that the problem apparently stems from severe base deformation. So, if any of you have been down this road before, my question is, what, if anything, can be done to minimize base distortion? I've tried water-dropping to make the alloy harder, and yes, it does help. But the base distortion is still there and if the boolits are made any harder, they will certainly only be good for shooting straight thru things. IE - no expansion at all.
Any suggestions? Can sizing have this great an impact on base deformation? Or should I just accept that not all boolit profiles are going to work in all platforms?

[Hannibal]

In response to a PM, the box the mould came in says 358-158-SWC. I am using White Label BAC lube with a gas check run thru a Lyman 450 sizer with a .358 die which size to .358, oddly enough. Alloy is a bit of an enigma, range lead, though it clearly is not nearly pure, as water-dropping makes a significant difference. I have never posted images here before, but if I can figure it out, I will do so.

It was not asked about in the PM but the bore slugs at .355" and the rifling is .345". The throat is sharp and abrupt, as is typical on lever actions.

[303Guy]

I've had boolit base distortion, including powder peening. What form of base deformation are you getting? I was able to eliminate it by changing powder, adding Dacron as a buffer and powder positioner and changing the boolit base design. You don't have the latter option.

Posting photo's direct from your PC is easy - provided they are small enough. I use photobucket which allows normal photo sizes to be posted onto Cast Boolits.

[44man]

It was not asked about in the PM but the bore slugs at .355" and the rifling is .345". The throat is sharp and abrupt, as is typical on lever actions.
These can't be right, bore is the small size and the rifling can't be .005" deep unless cut rifling. Groove size is what you want and is larger then bore.
Need a picture of base damage, most likely gas cut because they don't melt. Or slump from being too soft. If you want to shoot softer, use a GC boolit.

[Bigslug]

Get a wad punch and start making fiber cards or poly wads out of milk jug to go between your bullet and charge. Olde Schoole gas check. You can also put shot buffer, cream of wheat, or some other filler on top of the card to keep things in place. Just remember to work it up as a new load. This will likely improve your accuracy by not only reducing your base deformation, but by helping your powder ignite more consistently.

I myself am generally meandering in the direction of harder bullets and trusting the meplat to do the job for me. Going straight through? Not a bad thing. I was able to shoot some of my air-cooled ww/2% .44 Keiths - which aren't grouping great - at 1200fps into an evidence trap noted for not messing up the slugs, and noted that not only was there a fair amount of lead being dragged by the rifling back across the base edges, the bullets had a slight banana curve along their length. I've got to think they want to take a cold bath out of the mold.

[bedbugbilly]

Any chance you could post some photos? This is an interesting thread and we all can learn from it as well. I just started loading 357 for rifle and would like to see what is going on. Tjhanks!

[Hannibal]

It was not asked about in the PM but the bore slugs at .355" and the rifling is .345". The throat is sharp and abrupt, as is typical on lever actions.
These can't be right, bore is the small size and the rifling can't be .005" deep unless cut rifling. Groove size is what you want and is larger then bore.
Need a picture of base damage, most likely gas cut because they don't melt. Or slump from being too soft. If you want to shoot softer, use a GC boolit.

Yes, you are correct. Groove dia. is .355 and bore is .345. Measured off a bore slug with vernier calipers, so might be off .001" or so on the bore.
These were fired with checks on, no gas cutting evident on boolets recovered from a bullet trap of rubber mulch.

[Hannibal]

This should help, I hope.122061

[44man]

Very hard to tell, looked for skid and there might be a little but checks can pull in a catcher so they suffer impact damage. Then boolits will hit each other in a catcher.
What you see with the checks would not happen in the gun.
I really think you are looking at impact damage. To catch a pristine boolit is so hard to be unbelievable. I would not base anything on what you found.

[44man]

I am going to say the boolit just needs another velocity to work.

[Hannibal]

Since these were sized at .358", I wonder if sizing at .357" or perhaps even .356" would be of any benefit? The nonlinear dispersion between 25 and 50 yds. is what bothers me. 1 1/2" groups at 25 yds, opens up to over 4" at 50 yds.

[runfiverun]

base deformation is generally caused in the loading sequence.
either the case is too thick, or you are taking the taper out of it by sizing with a carbide sizer.
or are running it into a fcd type die squeezing everything together that don't wanna be squeezed together.

[44man]

Since these were sized at .358", I wonder if sizing at .357" or perhaps even .356" would be of any benefit? The nonlinear dispersion between 25 and 50 yds. is what bothers me. 1 1/2" groups at 25 yds, opens up to over 4" at 50 yds.
That is almost always a mismatch with velocity to twist. usually a small difference in diameter will not hurt so a little over groove is OK. just never under and actual groove size boolits will work. But you must spin the boolits. Too soft a lead will give fliers. Some nice and tight but a few way out.
I know and feel your pain but it will always be at your press where you find accuracy. The gun is fine. Ignore all the special dies and funny expanders. Ignore crimping separate too.
Understand each and every boolit has a different drive length and each needs a speed for itself.
I will say your bases were fine as they left the gun but spin is off. That boolit needs a work up.

[runfiverun]

non-linear dispersion like that can be caused by the velocity being too slow.
you are fine for the first 25 then the square boolit slows down and starts to lose stability.
it's pretty common for a wad cutter to fly very straight for 50 to 75 yds then just get all wobbly and lose accuracy.

[williamwaco]

You mentioned 358-158-SWCs. From the photos, I surmise you mean the C358-158-SWC Gas Check.

I don't shoot them in a rifle but I have found the TL358-158-SWCs to be one of the most accurate SWCs I have tested in revolvers and the TC .357 Mag
On the other hand I too have been dissapointed with the C358-158-SWCs ( gas check ).

I can see no reason for the unsatisfactory results.

[kir_kenix]

I also suspect that something may be going on during the load process. Can you explain/document your particular loading process? From sizing (measure your sized boolit, forget what the sizer says), to case prep, loading, crimping, etc? I had a friend having all sorts of trouble with a particular boolit...tried dozens of different things. LFCD being used here?

[Hannibal]

From what has been said above, it sounds like the common idea is to speed them up. Seems counter-intuitive, but I'm fairly new at this so I'll certainly give it a try. These were shot with 12 grains of 2400, so I'll starting increasing the charge 1/2 grain at a time and see what happens.

[Hannibal]

Load sequence : Starline brass resized and deprimed in Lee die. Cases primed with Winchester WSP primers. Flared in a Lee powder-thru die and charged with 12 grains of 2400. Lee 358-158-SWC air cooled boolet run thru a Lyman 450 lubesizer with a .358 die and lubed with White Label BAC lube. Mics at .358 when completed. Seated to the crimp groove and given a medium roll crimp with a Lee die. End of process. No FCD involved.

[KYCaster]

Those look more like full WC than SWC. I'm curious about the nose deformation rather than the base deformation.

If your boolit trap is causing the nose distortion then it can also be causing the base distortion.......

......but, is that rifling engraved on the nose of the second boolit? If that's the case, the nose is slumping in the chamber, which will easily cause the inaccuracy you describe.

Jerry

[Hannibal]

Those look more like full WC than SWC. I'm curious about the nose deformation rather than the base deformation.

If your boolit trap is causing the nose distortion then it can also be causing the base distortion.......

......but, is that rifling engraved on the nose of the second boolit? If that's the case, the nose is slumping in the chamber, which will easily cause the inaccuracy you describe.

Jerry
They are SWC, just look like wad cutter due to nose distortion from the trap. I have the boolets in my hand, and there is no nose engraving, just appears to be due to lighting/shadows.

[popper]

Not base deformation, nose is pushed back through GC on impact.

[fredj338]

I am not sure how you figure base deformation with bullets pulled from a trap. Many ones a bulet will yaw or even tumble in recovery media. With a gc, not even sure how one gets base deformation.
I have shot soft LHP into wetpack, the expanded bullets that travel straight show no base deformation.

[Hannibal]

Not base deformation, nose is pushed back through GC on impact.

I don't follow what you are saying. Would you elaborate some more, please?

[Hannibal]

I am not sure how you figure base deformation with bullets pulled from a trap. Many ones a bulet will yaw or even tumble in recovery media. With a gc, not even sure how one gets base deformation.
I have shot soft LHP into wetpack, the expanded bullets that travel straight show no base deformation.

And I presume you were not having any accuracy issues, correct? I am with this boolit.

[44man]

Rubber mulch is what I use and it is hard on a boolit. I use a plastic 55 gal drum full, on it's side, shoot into one end with a thick rubber belting screwed on over the hole. I have holes in the other end where revolver boolits made it all the way through.
Many are mangled from hitting other boolits. I need to empty it and redo but dang, I can't even roll it. I might cut the side out and start a new drum.

[Hannibal]

Mine is a 12"x12x"x48" box made of OSB. One side is hinged and I staple cardboard over one end. Stand it up off the side of the deck and shoot down into in point-blank. Boolits are easily and immediately retreivable. I am standing above the trajectory angles in case one comes thru a side, which has happened once. Any over-penetrations will simply go into dirt, which has not happened yet.

[popper]

Look at the dimple on the left GC. Like pushing dough through a drinking straw, straw is like the outside of the boolit. I recovered a GC from a 308 @ 2400 fps after it hit a rock pile (25'). Lead donut left in the check, dimple in the base of the GC. Other GCs were pretty mangled but all had the dimple, perfectly flat when loaded. One had cut through the gal. wire holding the yard sign, you could see where the GC hit the wire. Never did find any of the boolits. Got several 40TC from the same pile, one had half the nose sheared back 1/4", other side of the nose was just expanded a bit.

[geargnasher]

..... And while I am having success with a couple of other boolits, Lee 358-158-SWCs have been a colossal failure. ......Or should I just accept that not all boolit profiles are going to work in all platforms?


You answered your own question, or rather your rifle answered if for you.

Gear

[KYCaster]

Try shooting into fiber filled pillows. I've had very good results with handguns up to ~1400 fps.......not so good with 30 cal. rifles at ~1900+. Normally some abrasion on the noses, but mostly intact with very little deformation.

Tape two five gal. buckets mouth to mouth, cut the bottom out of one and loosely stuff with pillows. I use the really cheap ones from the local dollar store. Takes some effort to find and remove the boolit, but not as bad as sifting through sand or rubber.......and much better results.

Jerry

[williamwaco]

Try shooting into fiber filled pillows. I've had very good results with handguns up to ~1400 fps.......not so good with 30 cal. rifles at ~1900+. Normally some abrasion on the noses, but mostly intact with very little deformation.

Tape two five gal. buckets mouth to mouth, cut the bottom out of one and loosely stuff with pillows. I use the really cheap ones from the local dollar store. Takes some effort to find and remove the boolit, but not as bad as sifting through sand or rubber.......and much better results.

Jerry

Yikes, Will that really stop a .357 bullet?

[Hannibal]

Yikes, Will that really stop a .357 bullet?

His post says up to 1400 FPS. I chrono'ed some of my LBT 180s yesterday and they were around 1430 as I recall, don't have the chrono sheet in front of me. I do know they were going roughly 26" deep in the rubber mulch. And that stuff packs in pretty tight in a 48" box standing on end. I think I'm gonna have to pass.