OK - I took some pictures this morning. AUG Nato stock and trigger pack.
Took a new M3 PMAG, new Lancer AWM and a newer USGI with a new improved anti tilt Magpul follower.
Checked with and without the followers on clearance of the bolt catch and bolt.
USGI - no issue with clearing the bolt and the bolt catch was dropped out of the way due to the mag having the square opening. Also with a newer follower it has the bolt hold open feature after the last round.
Lancer AWM - no issue with clearing the bolt - again a nice square opening and also works for the last round bolt hold open feature.
Magpul PMAG Gen 3 - the wider opening on the Gen 3 is smaller than the Lancer and USGI but allows the bolt and bolt catch to clear and does allow the bolt hold open after the last round.
Magpul Gen 2 - sold all of mine due to this issue with SCAR and TAVOR rifles. Plus I have a few old Colts that the Gen 2 PMAGS don't drop free and the Gen 3 sometimes hang up as well. The more narrow opening for the bolt catch on the Gen 2 mags causes the bolt hold open part to ride up and get hit by the bolt carrier as it moves back and forth.
Last Round Bolt hold open - PMAGS have a shorter rear catch. You can see here the follower height differences. The factory PMAG Gen3 follower is shorter than their replacement anti tilt followers.
Dropping the mags out of the AUG did not drop the bolt - it stayed locked back for all mags.