Originally Posted by G20 lineman
I've been considering an aftermarket barrel for my G20 after reading about case support concerns. I got a glock because of the reliable reputation in conjunction with price but I'm wondering if an aftermarket barrel will take away from the factory reliability. are there other parts to that are needed to go with a 6 inch barrel that gives case support?
I think in general the aftermarket barrels do provide more case support (both with a tighter chamber and less of a cut where the ramp enters the chamber). Each aftermarket barrel is different in my experience, so it is tough to generalize much beyond the above.
I have a few KKM barrels that came with a tight throat and very little free bore, so loading lead bullets is a challenge for them. Another KKM barrel I have has a ton of free bore (as much as any of my stock Glock barrels), so reliable lead round feed is no problem.
I took a couple of my Storm Lake barrels to the range with me today to test some 10mm 175gr coated LSWC's and neither of them would feed these rounds (throat too tight), but my stock G29SF, G20SF and Kimber 10mm Stainless (1911) all fed them no problem.
If you plan to load your own rounds into nuclear territory (above max book), an aftermarket barrel may give you a few more loadings from your brass than the stock barrel, but you may or may not get factory stock reliability. If you are going to shoot commercial ammo, I would stick with stock. I rarely use my after market barrels these days. There is a reason Glock makes their chambers looser, deeper cut ramp, more free bore, it is all about feed reliability.