Piston vs Direct Impingement AR15 Testing

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…