Who innovated the direct gas inpingent system currently in use for several AR platform weapons, including the M16A2?
A) Ronnie Barrett
B) Richard Jordan Gatling
C) Eugene Morrison Stoner
D) John Moses Browning
God made all men, but it was Sam Colt who made them equal.
Not strictly speaking a handgun question, but I will take a shot at it
I am assuming that you refer to direct gas impingement systems, not to the specific details of the AR-15/M16 system. That being the case, my guess is the great John M. Browning. Of the available choices he is the most reasonable. (I do know who designed the AR-15, but he did not originate direct gas impingement systems.)