ProMag 10 10/20 mags malfunctioning

[botsdots]

Not sure if this is the right forum, but I'll give it a shot. I went to the gun show in Del Mar a few months back and picked up a couple 10 and 10/20 ProMag AR magazines. Two of them are malfunctioning and ProMag says they don't make 10/20 mags. They have "ProMag" stamped floorplates.

Has anyone else encountered ProMag 10/20 magazines? They look factory stamped on the body to limit acceptance of more than 10 rounds, so I find it hard to believe that someone else made them, but maybe someone is swapping ProMag floorplates, or they're knockoffs.

Unfortunately, I can't remember the vendor's name.

Thanks in advance.

[bigmike82]

Doh! Magpul != Promag. NM.

[apgegaspasser]

I purchased a 10/20 Promag for my ar build. I think I got it from Midway. As I was reading up on building my ar, I came across info on the Promags stating that they are known for having feeding problems. I took out my Promag and compared it to a Bushmaster mag I also had and noticed that the feed lips on the Promag were bent down slightly on both sides. It appeared to be a stamping error when they were made. What I noticed was at the front of each feedlip,the corner was slightly rolled over which would cause the tapered part of the shell casing to ride down and twist to the side which would not allow a cartridge to smoothly slide straight forward into the barrel chamber and would cause it to jam into the lugs where the bolt locks up with the barrel. I took out a small pair of needlenose pliers and bent them as straight as I could while trying to match the shape of the rest of the feed lips.
Check yours a see if yours have the same issue. If so it is a cheap and easy fix. After fixing mine, i haven't had any feed problems with mine. i hope this helps.

[Blue]

This is the one where the follower has cuts in the middle, and the rib in the side of the mag is pressed in right? I've got one of those and while it functions fine, it's a super tight fit in all of my lowers.

[apgegaspasser]

I'll have to look at mine when I get home. It sounds familiar. Does yours have a gray follower?

[brassburnz]

I bought a Promag 10/20 at Oaktree Gun Club about a month ago. They had a ton of them. Like Blue said, they are a tight fit in my Stag, Lauer and Rock River lowers. So I put it back in the plastic bag. When I can find the receipt and the time, I'll take it back to Oaktree.

[botsdots]

Ok. So it sounds like ProMag has 10/20s. I'm going to give them a call back. Really, I'm having two problems. First is a capacity issue. Second is two out of the four mags are double feeding. I end up with one round half-way in and second round right underneath it, both trying to get to their proper place. I think it's a feed lip problem because it happens at all spring pressures (10 in the mag and with 2 in the mag).

Thanks for the help guys.