Piston vs Direct Impingement AR15 Testing
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Piston vs Direct Impingement AR15 Testing
One of the things I have always wondered was how two identical AR15s would run with the only difference being that one is a direct impingement (DI) system and the other, a piston system. For those that are newer to AR15s, the vast majority of AR15s and military M16s run on a gas pressure bleed off port on top of…