I bought two boxes of Cor-bon for my modern AO M1 carbine. In the 15-rd magazine it fails to eject or load 50% of the time! Expensive experiment. I tried it in 3 different magazines and 50% fail to fire (total) every time. Woeful. Ironically, in a 30-rd magazine all 5 shots went flawlessly. So I loaded the rest (20 or so) in a 30-rd magazine and the hell with it. I greatly prefer shooting and handling the 15-rd magazines over shooting the 30s and I won't but Cor-Bon anymore. I fired 50 PPV JSPs in both types of magazines with about a 10-20% fail to fire. For FMJ I have about 5% failto fire, or 1-3 per 50 rounds, which I find irksome and pretty much random. That is, the fails to eject or feed do no appear to be ammo (brand) or magazine-related, it just always seems to happen at 1-3 per 50 rounds.
Oh, the problem with JSP is almost fail to feed. However, I recently got 40 SPEER gold dot JSPs and all 10 test rounds fired flawlessly out of a 15-rd magazine, not as expensive as Cor-Bon either, so that is my SD load.