Barrel extension denting shoulder junction

[montana]

Keep track of which side of the magazine the cartridge chambers from. It may be only one side of the magazine that could use a little smoothing..

[Klem]

DT,

Best mags? This topic comes up from time to time on the Forum and there does not seem to be a stand-out. To be fair I have only used ASC: 9, 16 and 24rd. The 9 and 24 have functioned flawlessly. The 16 (same size as 5.56 20rd) occasionally has the right-hand side round jam up into the extension. I had two but can't find the other one. Been playing with the lip but it may be the ejector.

Like Montana says, a lot can be fixed by servicing or changing mags.