Thank you all in advance for this forum. I just got my saiga 12 and finally had a chance to shoot it. The factory 5 rnd mag worked flawlessly every time. My Promag drums needed to be filed down a tiny bit to fit and had several failures in all three drums. Sometimes it wouldnt feed completely and the bolt be back about an inch, sometimes it would catch two shells at once, and sometimes the shell would be at too steep an angle and get caught in the chamber guide. It seemed as though the front catch was loose on all three and when i held the drum forward while shooting i had no problem. All the