Think I may have solved the problem with my AO carbine using the Korean mags.The carbine ran the best it has so far with the new mags, but I was still getting failure to pick up a round and eject. I'm thinking the mags need some tweaking or it's the South Korean ammo I have. Not sure how old the ammo is, there's no rust of corrosion on any of the rnds. Maybe I need to pick up a different brand and try it out.
Take a look at this photo. The "tits" on the rear of the Korean mags are higher than those of the OEM mags, making the Korean mags ride lower in the mag well the the OEM mags, thereby not picking up the rounds like they should. The Korean mag (stamped RO) is on the left:
Looking down into the well with the Korean mag inserted, there's about a 1/32 to 1/16" gap between the top of the mag and the top of the well. I can plainly see the difference on the rear of the mags. With the OEM mag inserted, there is no gap.
I was thinking there was too much side-to-side movement but now I'm thinking the Korean mags are dropping/drooping down prohibiting the bolt to pick up the rounds as it should.
Waddya think? I'm not sure what to do to fix it, other than buy more mags, nor have I been to the range to see what I can do (maybe place some tape from the bottom of the mag up onto the sides of the stock).
I put tape on both sides of all the mags to eliminate the side-to-side movement, not sure if I could maybe superglue a piece of brass just under the tits on the Korean mags to make them ride higher or not.