Leading

Dustin Cantrell · Jul 13, 2012

How do you guys avoid leading in your barrels when reloading with cast bullets?

I have four different lead bullets I've purchased through two different vendors. The 9mm bullets (.356) were 18 Brinell, 45 ACP (.452) 16 Brinell, 38 special (.358) 12 Brinell and 357 magnum (.358) 18 Brinell. I haven't loaded any of the 357 magnum yet. I've experienced what I consider a fair amount of leading with the 9mm and 45 ACP. It's a pain to remove though I haven't tried the Chore Boy trick. The 38 specials I loaded were fairly light to medium loads. Those leaded the barrel the least.

I'm assuming that the bullets are too hard for my application (moderate loads, not real hot loads) and are not obturating to seal and are therefore leading the barrel. I slugged the 9mm barrel. Well, kind of. I just took one of the 9mm bullets and tapped it through the barrel with a dowel rod. The bullet was not large enough to hit the grooves in the bore but the lands dug in a fair amount. Should the bullet fill the grooves or just be deformed by the lands? I didn't think it was supposed to fill the grooves because the pressure was supposed to make the bullet obturate to fill the bore.

I'm hoping somebody can set me straight here because I'm sitting on about 5k bullets and I want to either load these so they won't lead or buy the right bullets next time.

Scott Hearn · Jul 13, 2012

Yes the bullet should fill the grooves. The old school method of bullet sizing was to run your bullet size at least .001" larger than your groove dia. For example, .452" lead bullets for 45ACP while jacketed runs .451". It's just hard to get a commercial cast bullet to not lead. I haven't done it yet. And it's not too likely that you will get much obturation in low pressure pistol calibers anyway, full power 9mm and .357 mags maybe. Most commercial bullet casters run their alloy pretty hard because their customers want it. I'm really not sure why they do want that in handgun calibers because if you look in the Lyman cast bullet handbook 2200 FPS is pretty common in rifles with their #2 alloy which is about the same as the commercial casters are running. You just don't need 16/18 brinell to run 800/1000 FPS. One thing you might try is to run about 500 jacketed through the barrel first to smooth the rifling some. Also cooler burning powders will help. Titegroup is a real hot one. Some of the Vhit powders N320 and N340 are the coolest burning powders I've seen.

Iggie · Jul 13, 2012

Buy chore boy! I was having the leading problem and finally ran into some chore boy at the local ace b9ought all that was on the shelf (2 boxes) and oh wow did it turn removing lead into a breeze! I couldn't believe my eyes! I had several hundred rounds of lead through the barrel.. leaving streaks of lead it was bad I used to spend hours cleaning the barrel ... I tiny bit of one of the chore boy scrubbers enough to wrap it around the brush and 3 or 4 passes and there wasn't any lead left in the barrel at all it was cleaned! Its the answer!