A grim-faced U.S. Army major led a group of armed men away from a tropical village he decided not to attack. Wearing jungle boots and olive-drab battle dress, Edwin Brooks grasped a lightweight, reliable, .30-caliber weapon in his right hand as he walked.

It was an M-1 carbine.

The scene could have been anywhere in the South Pacific during World War II or somewhere near the Pusan Perimeter during the Korean War. But Brooks also wore a green beret with a Special Forces flash and he was leaving the then-South Vietnamese village of Ban Me Thuot in 1964, leading the indigenous forces he commanded back to base in an effort to defuse a rebellion.

It’s all on the cover of the January 1965 National Geographic magazine in a photo by writer and photographer Howard Sochurek. Not a single M-16 is anywhere to be seen. The Pentagon had shipped thousands of the new M-16s to U.S. troops including the Special Forces, but in 1964 many Green Berets still preferred the M-1 carbine, the weapon of their fathers’ wars.

What’s more, Brooks’ Viet Cong enemy was almost certainly wielding the more modern Kalashnikov assault rifle. As for the Montagnard tribesman Brooks trained and led, they also were carrying some of the 800,000 M-1 carbines the U.S. sent to South Vietnam during the war.

For more than three decades, the M-1 carbine did more than anyone ever expected it to do. Long overshadowed by the iconic and heavy-hitting M-1 Garand, the M-1 carbine began its existence in 1940 when the Secretary of War issued orders for the development of a lightweight and reliable “intermediate rifle.”

“It was a compromise,” Doug Wicklund, senior curator at the NRA National Firearms Museum in Virginia, told War is Boring. “They called it the ‘war baby,’ the younger sibling of the Garand, and it was for soldiers who were not on the front line, something that they would have a better chance of hitting the enemy and defending themselves with.”

The M-1 carbine was an alternative to the venerable M1911 pistol that was a proven man-stopper but demanded a fairly high skill level on the part of the shooter.

The success of the German Blitzkrieg in 1939 had convinced the Army that rapidly deployed maneuver forces such as airborne soldiers or armored columns could punch through front lines and endanger support troops. In theory, the M-1 carbine never was supposed to replace the Garand as a battle rifle—it was supposed to arm cooks and clerks.

But by 1943, up to 40 percent of some infantry divisions were carrying the carbine as their primary weapon, according to The M-1 Carbine, Leroy Thompson’s brief but thorough history of the weapon’s development and use.

In 1944, the Army modified the weapon to shoot both in semi-automatic and full-auto modes—and called it the M-2. It was one of the nation’s first assault rifles, spitting out bullets at a rate of 900 per minute.

During the same year, the Marines on Okinawa used a version of the M-1 fitted with the first U.S. night-vision gear—the so-called “Sniperscope,” visible in the banner photo at top.

“It was an easier gun to carry than the Garand,” Wicklund said. “It was shorter, it was lighter, it was reliable, it was easier to shoot and easier to clean and it had a 15-round magazine. It was easy to tape two magazines together and get 30 rounds to fire. Stopping power was not there with the carbine, but you could fire it more times.”

Once the United States entered into World War II, the Army issued contracts ramping up production of the M-1 carbine. Eventually, more than six million of the weapons in both semi-automatic and select fire models poured out of factories—two million more than the number of Garands produced during the war.

Winchester was one leading producer, but as American companies turned to war production Inland Manufacturing—a General Motors division and producer of a majority of the weapons—National Postal Meter, IBM and even Underwood Typewriter Co. cranked out hundreds of thousands of the carbines.

During World War II and the Korean War, it was completely possible for the Army to issue a company clerk an Underwood typewriter and an Underwood M-1 carbine.

When German troops received the history-changing MP 44 Sturmgewehr, the Wehrmacht put increased firepower in the hands of small units that could direct fully automatic fire at U.S. troops with an assault rifle. The M-1 Garand, hard-hitting as it was, carried only eight rounds to the MP 44’s 30 rounds contained in a detachable box magazine.

Inland Division produced 570,000 M-2 select-fire carbines as a solution. The weapon has a selector switch on the left side of the receiver and it can hold a 30-round box magazine.

It wasn’t a Sturmgewehr, but it was available. “The U.S. military has always used what it has already,” Wicklund said. “We had it in inventory. They were everywhere.”

It was also the ideal platform for a technological development that presaged how the United States would own the night during future wars.

Late in World War II, the Electronic Laboratories Co. developed active infrared night vision in the form of the Sniperscope, a 20-pound package of telescopic sight, infrared flood light, image tube, cables and power pack.

The scope had a range of around 70 yards and fit both the M-1 and M-2 carbine.

The system not only saw action in the Pacific Theater during World War II but troops used it widely during the Korean War. In nighttime battles, Marines packing carbines with the Sniperscope would fire tracers down on the positions of North Korean and Chinese troops, so machine-gunners could target the enemy with heavier fire.

Once again, the M-1 carbine was in the right place at the right time. One of the reasons the Marines selected it as the weapon of choice for the Sniperscope was the weapon’s modest weight and bulk. The lightweight carbine kept the weight penalty on an already heavy weapon system to a minimum, a boon for the G.I. who had to slog the battlefield with it.

This article by Paul Richard Huard originally appeared at War is Boring in 2014.

Image: Wikimedia