I bought new Galil mags from DSA and they will fire every round accept the last round. The last round is just low enough that the tip of the bullet hits the bullet guide and jams.
Tilting the mags up in the back as tight as they get don't rectify the situation, even though there isn't much play in bringing them up tight in the back against the mag catch. So essentially the front needs to come up just a tad or the bullet guide needs shaved on the bottom so that it sits on the trunnion just a little lower. Now, I am using the bullet guide from CarolinaShooters but my friend is using you