TheActivePatriot
02-21-10, 05:23
Got a C3 defense billet lower here (Yeah, I know, 6061 and not mil-spec anodizing, but it's on a dedicated varmint rifle so it really doesn't matter) that will drop PMags, but empty Okay USGI aluminums hang up. Normally you hear about this being the other way around. Measured with calipers, my PMags are equal or slightly larger in every dimension in comparison to the ten USGI mags I have on hand. Since it's just a varmint rifle and not a fighting gun, this isn't really a major issue, but it is puzzling. If there's enough clearance for PMags to drop free, and my GI mags are a hair smaller, what could be causing them to hang up?
ETA: Nevermind, I feel like an idiot now. 30 seconds after posting, it occurred to me to check the magazine catch. Sure enough, there's a burr on the mag catch that drags on the cutout in the USGI mags just barely enough to keep them in the magwell. Under close inspection, the PMags I tested in the lower all have a slight scratch above the mag catch cutout, where it would just scrape on through the polymer bodies instead of hanging up like the aluminum ones. Five seconds with a file and now all my mags drop free. Leaving the post up as info in case anyone else is having the same issue.
ETA: Nevermind, I feel like an idiot now. 30 seconds after posting, it occurred to me to check the magazine catch. Sure enough, there's a burr on the mag catch that drags on the cutout in the USGI mags just barely enough to keep them in the magwell. Under close inspection, the PMags I tested in the lower all have a slight scratch above the mag catch cutout, where it would just scrape on through the polymer bodies instead of hanging up like the aluminum ones. Five seconds with a file and now all my mags drop free. Leaving the post up as info in case anyone else is having the same issue.