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ShooterAZ
02-08-2013, 02:00 PM
Point in case is with 44 Magnum. I am getting some leading in the first 1/2-3/4 inch of the barrel, but only with the faster powders like Bullseye, Red Dot, and even with Unique. The slower powders 2400, H110, 296 I have tried don't exhibit any leading whatsoever, and in fact clean out the previously mentioned leading. I posted on this a while back, and someone mentioned that this was probably due to "boolit skid", and was related to "pressure curve". This problem has happened with both Lyman #2, and with a much softer alloy 1/30 with a small touch of antimony from the 95/5 solder.

Besides the obvious of sticking with the slower powders, I'm wondering how and if I can juggle my alloys to overcome this problem when using the more economical faster powders. Would 1/3/96, or 2.5/2.5/95 be more suitable? I'm not trying to load to "full magnum" loads, only 900-100 fps. I'm just trying to stretch out my stores of powder I have on hand until the component market comes back around. Any advise on this would be appreciated!

44man
02-08-2013, 02:36 PM
Try water dropping WW metal, that will help a lot.

ShooterAZ
02-08-2013, 02:43 PM
Sadly, I don't have any WW metal, next to impossible to find in my area. Would WD my 1/3/96 alloy be the next best thing?

44man
02-08-2013, 03:03 PM
Yes, let them age a week before loading. Size and lube and let them sit.

ShooterAZ
02-08-2013, 03:10 PM
OK, I will try that. Thanks.

303Guy
02-08-2013, 08:01 PM
You could try a fibrous filler to form a scrubbing wad under the boolit. I'd suggest sieved wheat bran or simply wheat germ, the latter being easier to get from supermarkets and is easier to meter.

runfiverun
02-08-2013, 08:03 PM
pressure curve could just be long enough to get past a tight spot and reseal the bore too.

lwknight
02-09-2013, 12:35 AM
Hard to see skidding a 44 bullet at 900-1000 fps. Thats only 45,000 rpm. That works out to less than 1/4 of the torque applied to a typical 30-30. Everything described sounds like skid though.
That is just a head scratcher! I can think of several possible scenarios but they are kinda out there.

Maybe the lube is not doing its thing right at the start.

Nocturnal Stumblebutt
02-09-2013, 12:48 AM
When I read this I immediately thought that it might be the lube, what are you using?

fcvan
02-09-2013, 01:10 AM
Lots of good suggestions. Lube, powder, fit and such. I would also throw in the suggestion of trying some plain based gas checks. There are lots of members who make them and share so that folks can try them. I don't stamp 44PB but m sure others do. Just my .02

ShooterAZ
02-09-2013, 10:15 AM
I'm pretty sure it's not a lube issue. I have tried White label BAC, CR, and 2500...all with the same results. NO leading with the slower powders. I'm pretty sure it is a pressure curve/BHN issue, and I'm determined to figure it out and overcome it.

fecmech
02-09-2013, 11:26 AM
Another thought is you might be getting some gas cutting and blow by with the faster powders before your bullet moves to seal the throat. According to the tech I talked to at Alliant, BE and RD develop their full pressure before the bullet leaves the case.

popper
02-09-2013, 11:31 AM
I agree with R5R - you get a thump, lose pressure when going into the forcing cone, skid and then leading. Try adding shot for arsenic and WD.

longbow
02-09-2013, 12:46 PM
Another option that is easy to try if you already have a bunch of boolits cast is to oven heat treat them.

Just put them in a metal contain or onto a metal pan of some sort, heat to about 475 degrees F (upper limit) for about 1/2 hour then drop into cold water.

If you have already lubed you could take a few and boil in water to remove the lube then OHT. Otherwise just cast a few and give it a go. OHT will make them harder than water dropping which is the only beneift... and you can OHT already cast boolits.

Longbow

williamwaco
02-09-2013, 02:01 PM
What is the diameter of those bullets?

I am expecting they are undersized.

I have been loading ".44 Special" loads on the .44 magnum since 1956 using Bulls Eye and Unique. In general it is one of the least troublesome cartridges for leading ( for me ).

Lube: From 1956 to about 2008 I used Lyman 50/50 but now I use LLA and have absolutely no leading with either. I use around 5.5 gr BullsEye or 7gr Unique.

ShooterAZ
02-09-2013, 02:22 PM
They cast at .432 and are sized to .431. They are undersized for either my TC Contender or my RBH. LLA is not an option for me, I hate the smell of it, and the stickiness. I'm going to follow the advise given, and try WD and OHT and see what happens. I will see if I can get my hands on some lead shot as well.

fecmech
02-09-2013, 04:37 PM
They are undersized for either my TC Contender or RBH
I believe you're gas cutting my friend. Shot my SBH for over 30 years with max loads of 296 and .430 bullets with never a problem. Tried shooting .44 special loads with BE and 231 and the leading started. I had .433 throats with .429 groove which evidently was ok at 35-40KPSI but not 10KPSI due to bullet bump up. Sized .433 with light loads ,no problem. You'll know if you go harder and the problem doesn't go away.

geargnasher
02-09-2013, 04:47 PM
I believe you're gas cutting my friend. Shot my SBH for over 30 years with max loads of 296 and .430 bullets with never a problem. Tried shooting .44 special loads with BE and 231 and the leading started. I had .433 throats with .429 groove which evidently was ok at 35-40KPSI but not 10KPSI due to bullet bump up. Sized .433 with light loads ,no problem. You'll know if you go harder and the problem doesn't go away.

I tend to agree most with this. If you're getting leading just at or past the forcing cone with fast powders/lighter loads and not with slower powders, it's most likely that you have a size issue. Thread choke can rear it's ugly head after switching to a powder whose peak pressure occurs well before the boolit gets fully engraved in the rifling. Insufficient pressure on the base of a boolit that becomes undersized after going past a restriction at the frame/barrel junction is apt to get gas cut at that point.

If the boolits are skidding enough to open gas channels along the trailing edge of the lands, they will lead the entire barrel, usually in the crevice between the side of the land and the grooves on the trailing side.

In this instance, I think harder boolits will actually be WORSE for leading, study post #7 again for the short, simple explanation. First thing I'd try is work up the loads to a little more pressure if it's safe to do so.

Gear

lwknight
02-09-2013, 05:16 PM
One thing that I did not see mentioned is cylinder size. The bullets could be getting squeezed before entering the barrel and it takes a bit for the bullet to abturate the bore with lighter loads.
Maybe the cylinders have build up at the throat?

44man
02-10-2013, 09:39 AM
Lighter loads have instant velocity, instant pressure. Most read "low pressure loads" but it is there all at once and it sure is not "low." This may NOT lead the whole bore because gas pressure drops fast.
Another misconception is that lube forms a hydraulic seal, sorry, not so.
Two reasons for leading at the cone and rifling start is skid for gas leakage or a soft boolit slammed into trying to turn or slump trying to size at the cone again. Lead gets scraped off. All kinds of "scrapers" can be come up with but you have ruined accuracy before a scraper can remove leading.
Experiments with my .430" groove and .4324" throats with 231 and Unique using .430" boolits has shown a tremendous increase of accuracy with no leading by making boolits harder. I have the best accuracy with 28 to 30 BHN.
Each gun can react different but it does not remove the fact that you must experiment. What I do might not be right for all but it has worked in my guns. I do not and will never believe in "bump up." I will never believe in a boolit over throat size. Bump up does not even work with a Minie' ball in a muzzle loader.
Gear mentioned thread choke but a boolit will lead more AFTER the choke. The choke makes a better seal at the start but even a slow powder will have a hard time bumping the boolit back to groove size and a fast powder sure will not. Best to find and remove choke.
Hard boolits do not lead more then soft as long as they are groove size or .001"+ more.

winelover
02-10-2013, 10:26 AM
They cast at .432 and are sized to .431. They are undersized for either my TC Contender or my RBH. LLA is not an option for me, I hate the smell of it, and the stickiness.

FWIW. Pick up an .432 or .433 sizing die and lube without sizing. Buckshot or Lathesmith can set you up.

Winelover

ShooterAZ
02-10-2013, 11:01 AM
Wow...thanks for all the good info. My RBH slugs at .4295...I meant to say that my boolits were not undersized. Sorry for the typo...looks like I may have been wrong on that one anyway. I just miked a few of my NOE 432-200-RF and a some of them are .433. I am going to pan lube some of them unsized and see what happens. Also, yesterday I cast and WD some of my 1/3/96 alloy. I have some really good things to go on now, hopefully I can get a handle on this. Now if it would just quit snowing, I might be able to go shooting.

Mal Paso
02-10-2013, 12:00 PM
My RBH slugs at .4295...

Have you slugged the cylinder throats?

ShooterAZ
02-10-2013, 12:35 PM
No, not slugged. A .430 boolit has very little resistance going through the cylinders. The .431 needs to be pushed through with a fair amount of resistance with the eraser end of a pencil. I just tried a .433 boolit and it won't go through at all.

Mal Paso
02-10-2013, 09:28 PM
.431" Throats and a .4295" Groove sounds like a good combination to me.

How hot are you loading them? I load Titegroup ang Clays for my daughter, 8-900fps, 5-6g, with good results. The top listed loads for Titegroup and HP-38 always used to give me leading. I use 2400 now for loads from 900fps to 1500fps.

I shoot .431" Boolits in Cylinders from .431"-.432" and Barrels from .429"-.430".