I have a G20. I cast and load lead bullets for my 40s. I tried the same bullet through my Glock barrel in a 10 mm load. I got no leading but the accuracy was 3 out of 5 shots in a piece of printer paper at 25 yards. I put my Lone Wolf barrel in it, and with the same loads, I could get baseball size groups in the center of the paper with no problem.
Jacketed bullets in my Glock barrel give me about the same accuracy as my Lone Wolf barrel at 25 yds.
I have no fear of damaging my gun shooting my cast lead bullets in the Glock barrel, but the lack of accuracy makes the aftermarket barrel well worth the money to me since I shoot mostly lead bullets.
Just my personal experience, yours may vary.
Edited to add that I was shooting from a solid bench using sand bags.
Make a hole
Last edited by plateshooter; August 23, 2012 at 08:41 AM.