Stop calling it DI - Why no one uses it anymore
This video, presented by a highly authoritative source on firearms mechanics, challenges the common classification of the AR-15/M16 system as 'Direct Impingement.' Instead, it argues, based on Eugene Stoner's patents and mechanical analysis, that the AR-15 utilizes an internal piston system. True Direct Impingement rifles, like the French MAS49, are contrasted with the AR-15's design where gas acts within the bolt carrier group.









