I have not handled or fired a Ruger AR. I have read a few articles. I have read one article that offered a brief firing report. I've no idea if the magazines are standard M-16/AR-15 pattern. It uses a piston rather than gas impingement which is practically an improvement. With a retail price of about $2,000, it is not inexpensive. Except for hard combat use, it may be a solution in search of a problem. JMHO. Sincerely. BruceV.