44 mag. cylinder leading at case mouth ?

[gray wolf]

Well I have another question about these revolvers and a little leading I am getting. My barrel stays clean and the accuracy is good, but I am seeing lead build up in the cylinder at the case mouth just before the throat begins. I guess you could say right at the spot the bullet exits the case and it's a pain to get out.
Throats are .432, bullet sized at .432 barrel slugs at .4295
The leading gets into about 1/4 " of the forcing cone also.
It seems what is going on in the cylinder is the offender.
If I can stop it there I think all will be OK.
This is with a mild load of tite group powder. I have tried 50/50 WW & PB
Air dropped and water dropped.
The thing that catches my eye is the crimp does not open and I think it is scraping lead and letting it build up at the case mouth, then carrying it to the forcing cone.
If I open the crimp on a fired case the bullet slides into the case body like it should, the crimp is a very light one.
I noticed that with 9.3 grains of Unique the crimp seems to open.
Am I not creating enough pressure in my loads to blow open the crimp ?
Should I try no crimp with the light loads ?
This has been on going and it needs to stop, it's frustrating me.
Put on the thinking caps men.


Sam

[Iron Mike Golf]

Maybe try a taper crimp against a drive band instead of a roll crimp into the crimp groove? You have good neck tension, right? You don't say what the boolit is or the charge is.

[gray wolf]

the bullet is #429421 only one I shoot.
6 grains of tite group, very accurate and also a light load, not much recoil.
Frictional fit of bullet to case is firm.
If I pull a bullet it is not reduced in size.

[runfiverun]

i shoot light loads in my 357 without crimps.
i watch how much case flair i put on them and can chamber them without removing it.
neck tension is more important than crimp.
the crimp is just there to keep the boolit from moving forward under recoil.
so you'll have to test a couple and see if they move under recoil.

[gray wolf]

Well I just popped a round from off the deck,
One round, no crimp, just removed the case bell. 6 grains of tite group.
could see lead at the beginning of the throat at the case mouth in the cylinder and the forcing cone had started to lead already.

[dragonrider]

I would try sizing to .431".

[MtGun44]

What lube? Maybe too hard lube? I frequently have a thin ring of lube the thickness of the case edge tapering
to zero at the point where the boolit size matches the throat, basically a casting in waxy lube of the
forcing cone, attached to the ejected brass. I presume that this is what protects that area. NRA 50-50 or
LBT soft blue.

Too hard a boolit? Keith designs crush a hair in the lube groove, pressurizing the lube immediately,
which is why that ring void (case mouth out to the full diam throat,(~1/16th inch) is filled with lube, it is being
pressurized in the lube groove. Too hard lube and or boolit for the pressure applied prevents this. Is you boolit
design a Keith? Flat bottomed lube groove or rounded? For light loads, not much crimp is required, so back
off a bit, and prehaps soften the alloy or change lube. Flat bottomed lube groove version likely to compress
better.

Bill

[geargnasher]

Well I just popped a round from off the deck,
One round, no crimp, just removed the case bell. 6 grains of tite group.
could see lead at the beginning of the throat at the case mouth in the cylinder and the forcing cone had started to lead already.

Try that exact same thing again with Unique after cleaning the gun again.

Gear

[44man]

I will get flack but the boolit is too soft, so soft it can't even iron off the crimp.
The test shot with no crimp shows the boolit is expanding into the gap between the brass and throat. Boolit damage and slump is the culprit.
First you scrape/size the boolit through an unopened crimp, then squish it back into the gap.
Pressure does not open the crimp, the boolit does.
Use straight WW's and water drop them. Age a week before loading and I bet the problem goes away.
50-50 needs oven hardened and a GC, still not best.
More pressure with a soft boolit will expand the base to the chamber walls along with the brass making a "plug" that might help open the crimp but it does not cure a slump or lead flow.
I have to ask if you are finding some lead spatter on the cylinder front too.

[gray wolf]

[QUOTE]What lube? Maybe too hard lube? I frequently have a thin ring of lube the thickness of the case edge tapering
to zero at the point where the boolit size matches the throat, basically a casting in waxy lube of the
forcing cone, attached to the ejected brass. I presume that this is what protects that area. NRA 50-50 or
LBT soft blue.
I am using a soft lube, my barrel has NO leading, not even after the frame window.
I have no lube build up on the cases,
The bullet is a 429421 with a round bottom lube groove. I get a lube star and some lube on the targets. the metal is not a hard metal it is my 45 ACP mix,
I have been melting down my 45 bullets cause that's all the lead I have.
So the lube is not hard it's soft.

For light loads, not much crimp is required, so back
off a bit, and prehaps soften the alloy or change lube. Flat bottomed lube groove version likely to compress
better.
I tried no crimp and one round leaded the cylinder right at the case mouth
also the the forcing cone, I get NO lead splash on the cylinder face or in the frame window.

Try that exact same thing again with Unique after cleaning the gun again.

Gear
That's the plan for this morning.
I have some Water dropped bullets that are hard, I will try them.

I have to ask if you are finding some lead spatter on the cylinder front too.
No lead on the cylinder face, just the beginning of the cone and the cylinder
at the point ware the bullet exits the case. Using no crimp did not help.
It's like the bullets were getting tore up as they come out of the case.
Lube is soft and doing it's job in the barre, 1/2" groups at 15-18 yards.
Yes the metal is soft.

Sam

[runfiverun]

looks like you have a couple of things to try.
just do one at a time and you'll see which one works for your situation.
change the powder, then the hardness.
then back to using a crimp.

[44man]

Lube sounds fine and there is enough left in the bore.
I have found no difference in GG shapes and have made molds for both.
The leading is confined to in front of the brass with carry over into the cone so the only conclusion is boolit hardness, not lube.
PB needs a hard boolit but even a GC boolit from soft lead will slump and the majority of the boolit has to squeeze through a crimp. The GC is not a cure-all. I have been making all my molds PB lately and they shoot fine up to 1800 fps and 55,000 psi pressure. They just need to be harder. I try to stay between 20 and 22 bhn but have gone to 30 for testing. Plain old WW's, water dropped work fine.
The very slowest powder for the velocity you want is always better because the fastest powders actually need a much harder boolit. Sounds strange but the sooner the thump, the more damage done to a boolit. Final pressure or velocity has nothing at all to do with it. You will see all kinds of pressure limits for alloys but that is wrong, it should be based on pressure curves. The peak pressure point for your powder should determine your alloy limit. Get over it, I am strange! :mrgreen:
I have been shooting my .44 a lot and had to clean it, the stainless looked like it was blued after 500 to 600 shots. I found zero leading-NONE, just enough carbon to cook a few steaks. I shot PB and GC from 265 to 330 gr. This old SBH is getting real close to 64,000 rounds and still shows no wear at all, just some sand blasting at the cone edge. The forcing cone is perfect and no throat wear. I swear a Ruger can not be worn out.
I have a million ideas and get in trouble a lot so I will only suggest a harder boolit. Maybe one more thing, use a standard primer in the .44 with any powder.

[gray wolf]

OK the primers are standard, no magnum. As I said I tried a round with no crimp and the cylinder had a lead ring just at the case mouth, the cone was leaded, all this from one round. Then I tried a shot with a harder bullet, the crimp tried to open and I still had leading--not as much but it was there.
All my test shots were one round test. bullets were .432--an easy push through the throat, no snap, just a snug fit.
Then I dropped the bullet size to .431, same powder same crimp.
Another mess with the leading.
This is work, shoot a round and then 20 minutes to clean for the next round.
Good thing I can light em off in the driveway.
So at this point I am not seeing any reel improvement but the harder bullet is the best of the bad shows so far.
So the last test was with 9.5 grains of Unique, Med. crimp, same bullet.
The case mouth gave up the crimp and a bullet would slide in and out with just a little effort. The cylinder showed very little lead and was clean with a brass brush and a dry patch. The cone had about 1/4 of the lead splash and also cleaned up with little effort.
So my conclusions are that the tite group was to much of a blast at the onset of firing, and hit the soft bullet to hard, the unique though a hotter load gave the bullet a softer push and longer follow through.
I think the answer so far from what I have seen is a slower powder and to water drop my bullets. Not saying plain WW air cooled wouldn't work.
But my bullets are melted down 45 ACP bullets that started as WW but were cut with PB in order to stretch it out.
However they do harden up if Water dropped.
So my plan is to save the mild tite group loads for the 45 ACP
Use the Unique for the 44 with a harder bullet. All this I can't do today but that is my plan so far.

[44man]

That is better. Just experiment. Read between the lines for all of our posts, mine too, until you get results.

[Cadillo]

Just today I shot my .44 Spl Bisley and found that my cylinder is running quite a bit cleaner in the leade and throat areas since I started loading cases that are neck sized only. The chambers of my gun are quite large, and it seems that the bullets start out with poor alignment when full length sized. Checking my chambers, fired cases, and loaded ammo with pin gauges and a micrometer show a significantly better fit of cartridge to chamber when neck sizing.

It might be worth a try with your gun and ammo.

[Cadillo]

Gray Wolf, I just read your latest post here and you and 44 Man have convinced me to try Unique in my .44 Spl loads. Hopefully it will be an improvement over 231 in this area.