All of the .223 style choices and less pop.
I was going to suggest a rifle length AR (A-2), but the OP posted in the "Bolt/Lever/Pump" forum.....
Way back when dirt was the newest in new, at BRM in the third week of Basic Training, one of our DI's demonstrated the complete lack of recoil of the M16a1 rifle by putting a 30 round magazine downrange through one on FA, with the buttstock against his crotch, while he held the gun w/ both hands by the pistol grip.
With GI earplugs in and your cheek against an A-1/A-2 style stock, the "D-oing!" of the buffer spring is louder than the "pop" at the muzzle.