I've been hit or miss with MAG brand mid-caps in my G&Ps.
I always do the tape/velcro trick which clears up the problem.
I've owned 3 G&P M4s and I haven't had any luck with MAG brand magazines. They fed great in my G&G, but haven't worked for me in my G&Ps. I've used mostly G&P metal mid capacity magazines and I now use Socom Gear 190rd Troy Battlemags (same as Pagan). They feed every round and have a high capacity for a mid cap.
Last Edit: Apr 30, 2014 12:16:56 GMT -5 by Gunny87
G&P MK23 - SMP G&P MK18 - STAR FNC x2 - Tokyo Marui MP5 - CA M24 - UTG M3 - Cybergun M&P 9