I used to load 230gr 45acp cast from wheel weight lead, water quenched, lubed with Lee Liquid Alox, at a little under 800 fps. I also used to load 180 grain in 10mm at 40 S&W velocities, same lead, same lube. I never had any visible leading whatsoever, and I shot up to 300 rounds at a time. Never saw any signs of overpressure in my brass or primers, either. I suppose there must have been some leading, but it couldn't have been more than copper fouling.
I'm not saying Glocks haven't blown up with lead ammunition. They've blown up with jacketed ammunition, so I'm sure they've done it with lead. 1911s do it, too. I've seen a barrel blow out on a semi-auto Thompson with factory jacketed ball ammunition.
Yes, there is a possibility that a low pressure, low velocity lead round could cause my Glock 20 or 30 barrel to rupture. I'm thinking it's about as likely as the possibility of my Glock 23 blowing on a 40 S&W jacketed factory round. Or the possibility of it happening to one of the guys shooting 9mm major in IPSC.
But if you don't like the odds, or you disagree with my assessment of the odds, don't do it. It's a free country.
