I went shooting yesterday, and I took the last NIW USA 40 round mag I had.
It fit into my OLY no problems.
The first 40 rounds it worked perfect.
The second 40 rounds it worked perfect.
The third 40 rounds it worked perfect.
The fourth 40 rounds it started to jam and misfeed.
After I loaded 35 rounds for the fifth time the weld at the top of the mag let go, then there were 34 rounds on the ground.
The next thirty rounds came from my USGI 30 round mag (via my AR15) into that 40 round USA mag.
Verdict:
The USA 40 round mag makes a crappy AR15 mag. The USA 40 round mag makes a great target at 10 feet!
GEF

I have a USA 30 rounder for my mini 14. It has never failed to fail to feed.

I wasn't cheep either. I think I paid $40.00 for it, NIW, at my local FFL when I bought the gun. If they are going to go through the trouble of making something, why the hell didn't they just do it right?

I never thought of using it for target practice though. Maybe next time I get my daughter to the range, I'll let her have her way with it with her .22. :)

I have shot allot of rounds from the USA 30 rd mags and have never had a problem.  But with the colt 20 rd clip that I have it fowls constantly.  Horse apiece.
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