MILITATED

Might be worth noting that they worked with a Masada ACR. Part of the mag had to be modified but not a part which would effect it in an M4 - unmodified ones also have the same problem.

Got no idea, bought them off a mate after they were found in a box. He can't remember either, and they've got no indication as to what company made them.

Bit weird... Just stuck a bit of electrical tape under that hole and it holds the mag in better. Dunno how it will feed though. Will try it after. Update: BBs don't feed either, but feed from other mags. Maybe they're just not meant to be

From measuring the holes in the mag where it catches, I noticed that the PMags hole is 1mm smaller in terms of their height if that makes sense. Could that possibly be the issue?

King Arms Blackwater BW15 Carbine. Tried it in one of my friend's G&G Raider and it does the same thing. Other mags work fine though.

I've recently bought a few PMags, but I am having a slight problem with them. They will not lock into the magwell; they just don't seem to catch. I've tried them in two different guns (one of which I have seen PMags in before), but they have the same issue. Standard magazines fit just fine and lock in on both guns, so why won't these? You can literally just pull the mag with very little force and it just comes out.