In 1953, U.S. Army Lt. Col. Roy Rayle took up his new post at Springfield Armory. Best known for his work on the M-14 rifle and M-60 machine gun, he spent his time at the government arsenal taking part in several different projects — including the development of the T-148 grenade launcher.
Marshall found that commanders gave extra grenades to soldiers they saw as having the strongest arms, regardless of how well they could actually toss the small bombs. Officers were dismissive of rifle grenade launchers — a device attached to the front of a rifle that lobs grenades at longer ranges — and individuals who had skill with them.
This 40-millimeter cartridge was something of a revolution. The projectiles only armed after they flew, spinning, away from the barrel — making them relatively safe to carry and shoot.
Each 40-millimeter round weighed eight ounces. This was enough for the shooter to feel the weight of the whole gun shift as they fired one grenade after another — easily throwing off a person’s aim.
In addition, Rayle and his fellow weapon designers had started work on a backup launcher. This weapon — dubbed the XM-79 — was a crude, but simple single-shot grenade gun that worked like a break-action hunting shotgun.
As American troops — especially elite Special Forces soldiers — began heading to South Vietnam in greater numbers, many arrived carrying the final production version of the M-79. A small number of T-148s made it onto the Southeast Asian battlefield, too.
This article by Joseph Trevithick originally appeared at War is Boring in 2017.