I needed to place a lighter spring in my complete sized M16 A2 clone but it ran great. Tried out once again With all the eleven.5" Comando Colt higher. No dice. Ran 500 rounds of wolf by it nowadays. Didnt damage the spring in the least.I attempted a lighter H1 buffer and an extremely weighty 8.2 ounce . The H1 exact same factor as well as the 8.tw