Well, read through the link I posted, mags could be sitting too low, symptomatic with some WASRs.
Also follow sd_shooter's words of advice and do some measurements, as well as, MrPlink's, start with the basics again, eliminate the mags.
"If the American people ever allow private banks to control the issue of their currency, first by inflation, then by deflation, the banks & corporations that will grow up around them will deprive the people of all property until their children wake up homeless on the continent their Fathers conquered. The issuing power should be taken from the banks and restored to the people, to whom it properly belongs."
KrisAnne Hall on Oregon
"I am sullied - no more" Col. Ted Westhusing