I had 2 20 round pro mags for my mini 14 and they would kick shels if i put more than 5 in them. the mags look bad ass but they where the most useless mags i have ever owned and have 25 FAL mag, 6 Jericho 40cal mag, 9 mini 30 factory mags, 4 ruger MK2, 15 30 round AR mags, 12 1911 mags. and some more.
I bought a Pro Mag 20-round blued steel mag, and I'm taking it back. The follower won't activate the device that holds the bolt open, and the fit is too sloppy. I didn't want to try shooting with it.
USE ONLY RUGER FACTORY MAGS!!!!! Others may work but for some reason the factory mags seem the absolute most reliable... so why waste money just to take a chance on what might not work.