This was a factory 10 round PMAG (not modified and not one of those fake ones) in a sealed container.
So I picked up a 10 round PMAG today for bench rest shooting today. I created a dummy round for a reload I had planned. It’s a 77 SMK using the Sierra Reloading Data COAL. I had the COAL dead on and when I chambered the round (using the 10 round PMAG) it jammed…badly. The CH and BCG were stuck forward. So I separated the upper and lower receivers and had to use a rubber mallet to knock them loose and have the round extract. I tried seating it deeper and…same problem (even though the COAL was fine). I tried it a few more times (same problem and same solution whether using the CH or bolt release to chamber a round). Now just for the hell of it I tried a 30 round PMAG (Gen 1 IIRC). It chambers and extracts like a charm, and I tried it numerous times and not a single issue.
I’m a bit concerned about such a dramatic failure (and I’m happy it occurred at home with a dummy round and not a live round. I’m also happy I was able to diagnosis the problem and solve the issue (using some internet research).
So my build was
BCM Lower and Stock (might switch stock)
BCM Midlength 16 inch upper
BCM BCG
BCM Ambi CH
Magpul BUS
Magpul Vertical Grip
Magpul Mid Length Handguard
I’m curious about this as well. I have one on order that should be here soon. I will definitely test with dummy rounds before taking it out to the range with live ammo.
I can guarantee you Magpul would have been perfectly happy to replace it for you with a functioning unit with or without a gun forum thread griping about it.
