Vern Humphrey
Member
My company (A-1/61 IN) had two. Both had standard short cylinder bore barrels. The Army may have experimented with shaped muzzles, but I never saw one in the field.I have it on good authority that at least in the jungles of Vietnam the 12 gauge was fitted with a device called a "duckbill" which made it a better defensive weapon. Ergo you can only claim military preference if your weapon has that device as well.
The Army also designed a shotgun shell for the M79 Grenade Launcher. It was essentially a sub-caliber device, a 12 gauge chamber in a 40mm grenade case. Designed for self-defense use, it wasn't worth a flip.