Originally Posted by
gloob
I don't doubt that TG was the problem. But when YOU load your buddies bullets, you're not just switching the powder, are you? Don't you have your own dies, too? Since this is 9mm, case-swaging is a very real problem, not a myth.
As for the "slug your bore," crowd, there's a significant amount of people who do not have the tools or ambition to do that. But if your fouling is not TOO bad, you might try shooting a jacketed bullet and examine what if any fouling is left. If you are left with fouling just in the grooves and not on the lands, then your groove size is at least larger than jacketed OD. You can also just see if larger bullets fit in your chamber, first. It doesn't really matter what you find by slugging a bore, if you can't fit larger bullets in your gun, anyway.