Im wondering about the life expectancy of a glock barrel. i have a g19 with several thousand rounds through it. further im looking into buying a 40 cal, g22 or g23, from a local pawn shop. they are police trade ins, and they have a bunch here in phoenix. im wondering how many rounds you can put through a 9mm and 40cal respectively, before needing a barrel change. Thanks Wanna kill these ads? We can help!