I got 5 of these from Amerisurp, and 2 of them were WAY too tight in the mag well. I mean shove-in, yank-out tight. Some might be OK with this "feature," but I am not.
It turns out the mags are out-of-spec (long) in the front-to-rear direction. I took a file to the top 3 inches of front and back at the seam, which seemed to be the high points. This required filing down past the anodizing. Took a bit off each time and kept checking for fit, and eventually the mags were found to drop free. I was fortunate enough to have a can of Permaslik G on hand, and now these formerly worthless magazines look great and have a new lease on life.
I'm aware the filed-down areas are now more prone to wear and tear, so I'll probably designate these mags as practice-only. Mostly, I'm happy to salvage the $22 I thought I had thrown away on these 2 bad magazines.