In 1932, the Army ran another trials program to select and adopt a self-loading infantry rifle to replace the Springfield. This time, the playing field was dominated by only two serious contenders: John Pedersen with his T1E3 rifle and John Garand with his new and improved T3E2, both in caliber .276. Pedersen’s de­sign used a toggle-delayed blowback mechanism with the breech locked by a sort of knee joint during firing. Garand’s design used a more conventional rotating bolt driven by a gas piston, which tapped expanding powder gases from the muzzle to operate the action. In the trials, John Garand’s rifle was found to be more robust and reliable than Pedersen’s and had one crucial advantage—it didn’t need lubricated ammunition. By virtue of its delayed-blowback operating mechanism, John Pedersen’s rifle would seize up and stop functioning unless the cartridges were lubricated, but its internal lubrication system increased complexity and allowed dust and grit to accumulate in the receiver, eventually causing malfunctions without careful cleaning.

The Army also had been testing the prototype rifles not in the standard cham­ber­ing of .30-’06, but in an experimental .276. Military analysts had already de­termined that the new cartridge had a number of advantages suiting it well for use in a self-loading infantry rifle. Somewhat smaller and less powerful, the cartridge placed less strain on a rifle’s operating components and produced significantly less felt recoil, allowing soldiers and Marines to fire more rapidly and accurately. Furthermore, the lighter weight and lower production cost of each round allowed men to carry more ammunition into the field and stay in the fight longer.

During the late stages of testing, Gen­eral Douglas MacArthur personally inter­vened to throw a proverbial wrench in the whole program. Wary of the additional complications a new infantry cartridge would pose for the U.S. military’s logistical network, MacArthur ordered that the .276 be abandoned immediately and all rifle development focus on the standard .30-’06. John Pedersen had designed his rifles around the .276 cartridge, but Garand had an ace up his sleeve—he had been working with the .30-’06 for longer. One of his crucial advantages was that he could readily redesign his T3E2 in .30-caliber, whereas Pedersen could not as easily scale his own designs up to fire the more powerful round.

This Garand prototype, designated T3E2, competed in U.S. Army trials beginning in 1932. It features a primitive “gas trap” system which taps expanding gases from the muzzle rather than the simpler and more efficient gas port arrangement found in most production M1 rifles.

Although Pedersen was known across the developed world for his design exper­tise, Garand’s rifle proved more effective and easier to manufacture. It was officially adopted as “U.S. Rifle, Caliber .30, M1” by the Army on Jan. 9, 1936.

The Marine Corps has traditionally been a little more conservative than the Army with adopting new rifles. Marine Corps brass in the late 1930s saw the rapid-fire capability of the Army’s new rifle as nothing more than a great way to waste ammunition and impede precision marksmanship. Despite their initial skep­ticism, the Corps ran a trials program of its own in 1940 to determine whether a semi-automatic rifle could be better than the venerable Springfield. They tested Pedersen’s and Garand’s designs along with a recoil-operated rifle designed by Marine reserve officer Melvin M. Johnson.

The Corps eventually decided to send some Johnson and Garand rifles to the Pacific theater to see how viable they were in combat. Both rifles, especially the Garand, quickly proved their worth against the Japanese in battles like Guadal­canal. The Japanese had long used the banzai charge as a way to dislodge enemy forces, and this tactic worked very well against Chinese conscripts armed with slow-firing Mausers. But against highly trained U.S. Marines with semi-automatic M1 rifles, a bayonet charge never stood a chance. Far from wasting ammunition, the sheer volume of fire provided by the new rifle allowed Marines to suppress enemy defenders and make rapid follow-up shots at moving targets.

Hearing positive feedback from Ma­rines who had used the M1 in combat, the Marine Corps formally adopted the rifle to completely replace the M1903 and began mass issuing the new rifle to Marines in the field in early 1942.

Recall that John Garand was a pro­duc­tion engineer with a great deal of ex­perience designing factory equipment. This background allowed him to design the rifle for ease of production as well as the machines that would perform each operation. This proved to be a key factor in giving the United States an edge during World War II. They could manufacture and field in the mass quantities needed, something that tripped up the likes of the Soviet Union and Nazi Germany with their own self-loading rifle programs.

With America’s industrial might at their backs, riflemen of the United States Ma­rine Corps used the M1’s fire superiority to fight their way all the way across the Pacific. Marines carrying M1s raised the American flag over numerous islands, and when war broke out on the Korean pen­insula in 1950, soldiers and Marines picked their M1 rifles back up and went to go fight.