I have a saiga .308 converted AK that is acting up. Today I fired 2 25 rd surefire mags through it. All I could do was a double tap and the next rd would either not load all the way or the last double tap rd wouldn't eject. On both magazines the last 8-10 rounds went through as fast as I could pull the trigger. Any ideas of what could be the problem and how much I can expect a Gun smith to charge to fix it?