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tding
04-11-2007, 08:40 AM
:???:
Being new to both casting and reloading I don't understand why gas checked moulds are available for the 9mm and 38/357 boolits but do not seem to be available for 40 S&W or 45 ACP.

Since I have only cast from WW I am concerned about leading. Everything I read says that gas checks will help to prevent leading, especially with softer alloys.

What is the story?:confused:

NVcurmudgeon
04-11-2007, 10:25 AM
tding, availability of GC designs seems to be directly connected with velocity potential of the respective cartridges. The .357 and .38 Special can move a cast boolit into the velocity range where leading can become a real problem. The .45 ACP is notorious for low velocity. A very popular .45 ACP mould is Lyman's #452374, which duplicates the 230 gr. GI roundnose jacketed bullet. They do, or did make a gas check version, #452484, which has been enthusiastically comdemned as unnecessary by several members of this board. Who needs a GC at 830 fps? I can't comment about .40/10mm pistols because .30, 9mm, .38, .44, and .45 keep me too busy to even think about adding still another caliber!

Black Prince
04-11-2007, 09:18 PM
tding

Being new to casting, you don't know that the big bugaboo of leading is a problem you are not likely to have. I cast wheel weights also and lube with alox/bees wax. I shoot 15 to 16 grains of 2400 and a 173 grain (as cast from my alloy and lubed) Lyman 358429 plain based Keith bullet. I've NEVER had a leading problem and that bullet comes out of the barrel on my 6 inch Smith at 1200 FPS over the Chrony.

Gas checks may have some application if you also shoot a .357 Herrett like I do and I solve that with a gas check and reduced loads or jacketed bullet. The Herrett was designed for jacketed bullets at full power so when you reduce the load, the accuracy is also reduced. At least, it works that way in my Herrett and every other one I know about. I decided that cast bullets are not the best bullets to use in the Herrett.

Cast and shoot a bunch of bullets and see the results before you go worrying about a problem that you are not likely to have in a handgun anyway.

It is a different story in longer rifle barrels, but let's not go there with this discussion because it's an entirely different set of circumstances.

You may try droping your cast bullets into cold water to quinch them and thus make them harder but only do that if you are going to pan lube and shoot them in as cast diameter because you work soften the sides of the bullet if you then run it through a sizing die. Or you may size the bullets to say .358 , then run them in the oven at about 400 degrees ( or just before they begin to slump) then dump them into cold water to harden them. Then run them through a .359 size die to lube them which will not make them softer since the die will not move any metal.

At most velocities that you are going to get from handgun barrels, you are not likely to have leading problems unless you have a rough barrel. If that is the case, the problem isn't your cast bullets.

Casting your own bullets can be fun and it sure does lower the cost of bullets. It is not black magic or most of us who do it, couldn't. Just try it first and you'll gain confidence to do whatever you want once you see that it's no big deal. In my opinion, gas checks are needed only for rifle bullets, and I do not use any for handguns. I share that view with some experienced casters and shooters such as Elmer Keith who knew a thing or two about the subject.

Go for it and let us know how it works for you. Good to see you here and welcome. If push comes to shove, I live 55 miles north of Atlanta at Big Canoe. ( Google it and look it up.) If you have problems, let me know here on this forum and we'll meet at the Pickens County Sportsman's Club shooting range near Jasper and I'll help you, but I tell you it's not a big deal.

454PB
04-11-2007, 10:25 PM
"You may try droping your cast bullets into cold water to quinch them and thus make them harder but only do that if you are going to pan lube and shoot them in as cast diameter because you work soften the sides of the bullet if you then run it through a sizing die."

If the quenched boolits are sized quickly, they will harden just fine. The hardening process takes some time, and takes days or even weeks. I'm not a fan of quenching, but when I do it, I size them within an hour or two.

In my handguns, I've found that velocities over about 1300 fps. require gas checks. Many of my loads in .454 Casull are over 1500 fps, and I've not found a plain based boolit yet that will handle that velocity (and pressure) without leading and deformation.

Bret4207
04-12-2007, 08:57 AM
There's also the question of pressure, case design, throats, barrels, etc. The old example was you could run a 30 Carbine at full house pressure with a PB boolit in many guns with little or no leading. Try the same thing with your 03A3 and you'd better have a quart of mercury on hand. Cast booilts are an ART, not a SCIENCE.

As a general rule I can take straight WW PB boolits up to 1200 feet or so in a 38 or 44 cal peestol. But I have issues with the same alloy once it passes that speed or if I pass 1400 in a rifle. Thats a gross generality. My advice is start low and work up and SEE what happens. If you can get away with a PB design go for it, 'cuz it's a lot cheaper and less of a hassle to use PB than GC designs.

Black Prince
04-12-2007, 09:50 AM
tding

You did not ask about cartridges capable of generating velocities above that which will lead while shooting wheel weights in standard handgun barrel lengths. Use any commonly available lube with your wheel weight bullets in the cartridges you asked about and you'll be fine.

As Crudmegon said," it seems to be directly connected with velocity potential of the respective cartridges."

THAT is the issue and it is a non-issue because the velocities related to the cartridges you specifically asked about are not going to be sufficient to lead your barrel while shooting wheel weight bullets in standard handgun barrel lengths.

Once you cast, load, and shoot a batch of bullets, you'll ask yourself why you were uptight about it because you'll discover it's no big deal. It is normal however, to have questions the first time you try it. If this were rocket science, most of us doing it now would not be doing it. Just do it and let us know how it worked for you. Ask other questions as you have them. We will help you when we can.

BTW, if you are going to be shooting cast bullets at the higher velocity end, especially if you shoot revolvers, you may want to get a Lewis Lead Remover. It will QUICKLY remove any lead from barrel, forcing cone and chambers should you have any. It is not expensive and comes caliber specific. It does not have the potential hazzard that using Mercury has. Find it here http://www.brownells.com/aspx/ns/store/productdetail.aspx?p=21587

Every now and then I'll get some leading in my 44 mag. Smith and Smokey using cast bullets and the Lewis Remover quickly solves the problem. It's not a big deal.