At first glance, the relatively straight, rimless case of the .30 Carbine may lead unknowing shooters to believe the ammunition was designed for a pistol. Afterall, it looks more like a handgun round than one made for a rifle, but that’s not the case. No, the 7.62x33mm round was created as a light rifle cartridge originally requested in 1938, and would eventually become the most produced small arm for the U.S. Military during the Second World War. The .30 caliber cartridge features a round nose lead bullet with a diameter of 7.62mm, or .308 inch. The slightly tapered case has a neck diameter of .331 inch and a base diameter of .354 inch. The case has a length of 1.290 inches and an overall length of 1.650 inches. Designed by Winchester, the ammunition features a small rifle primer and has a maximum pressure of 38,500 pounds per square inch (psi). In its original form, .30 Carbine ammo has a 110 grain full metal jacket (FMJ) bullet that reaches a velocity of 1,990 feet per second (fps) and an energy of 967 foot pound (ft·lb) force. Although it’s most often referred to as the .30 Carbine, shooters may also come across the ammo labeled as: .30 M1 Carbine .30 SL (where SL stands for self loading) .762x33mm .30 Cal ammo .30 Cal Carbine ammo M1 ammo .30 ammo The Development of .30 Carbine Ammo It was 1938, and the U.S. military had received a plethora of reports from the field. The M1 Garand rifle, the standard long-gun of the Armed Forces, was simply too cumbersome. It was large. It was heavy. And it got in the way of soldiers, impeding their mobility. The Army needed a carbine, something that proved to be a better warfighting tool, specifically for its ammunition carriers, machine gunners, mortar crews, and administrative and communications personnel. It needed more range and power than the M1911A1, the Army’s standard issue .45 ACP pistol, and it needed to be lighter than the M1 Garand. It was this need that led to what has become known as the “light rifle project.” Finally, in June of 1940, then US Secretary of War Henry Stimson ordered the development of a lighter rifle. The request included that the carbine weigh five pounds or less (which was about half the weight of the M1 Garand rifle and Thompson submachine gun) and fire a bullet with a diameter of at least .27 caliber. At 300 yards, the bullet should remain effective and have a mid-range trajectory ordinate of 18 inches or less. While different firearm manufacturers set out to create the new weapon, Winchester was contracted with the job of creating the ammunition. Edwin Pugsley, a designer at Winchester (and, irrelevant to his ammunition career, the inspiration for the Addams Family character, Pugsley), took the self-loading .32 Winchester cartridge, turned the rim down, and used it as the base for the new cartridge. He fitted the rimless case with a round nose .308 caliber bullet. Like the military issue full metal jacket ammo for the .45 ACP, the lead bullet was covered in copper. The ammo, from its first production, propelled a bullet weighing 120 grain (gr) at a velocity of 2,000 fps. The first 100,000 rounds were head stamped with “.30 SL” for self loading. This lighter bullet, which contained more modern powder than its predecessor, traveled 600 fps faster and was 27 percent more powerful than the .32 Winchester self-loading ammo. From .30 Caliber Ammo to M1 Carbine While Winchester was focusing on .30 Carbine ammunition, the company was also working on its Model M2 Rifle chambered in .30-06 for the military. Because of these projects, the firearm manufacturer didn’t provide a prototype for the U.S. Ordnance Department’s “light rifle project.” Even though multiple carbines were tested, none of the prototypes made the cut. Some failed in accuracy, while others didn’t come close to meeting the requested five-pound weight limit. Army Colonel Rene R. Studler, who was also the Chief of Research and Development of Small Arms, convinced Winchester to modify its current project, the .30-06 Model M2, and scale it down for the new .30 caliber cartridge. Winchester did. And 13 days later, the company showed up with its prototype. It was a success, and the M1 Carbine was officially on its way to manufacturing. Initial Army testing began in August of 1941. After proving its effectiveness, mass production of the M1 Carbine began. And over the next few decades, over six million M1 Carbine firearms were manufactured. Although Winchester created both the ammunition and the firearm, they weren’t the top producer of the M1 Carbine. On December 8th of that same year, the U.S. military joined the war in the Pacific. Three days later, on December 11th, Germany declared war on the U.S., entering the nation into the European battle. The country was officially a part of World War II. Entering into the war meant more guns were needed – more than any one gun manufacturer could create. Industries all over the country set aside their products and started providing weapons the military needed, including the M1 Carbine. The Inland Division of General Motors was the top producer of the light rifle, Winchester the second. Other notable M1 Carbine manufacturers included IBM, Underwood Typewriter Company, and Rock-Ola Manufacturing Corporation, which was made famous for its jukeboxes. The M1 Carbine was issued to infantry, machine gun, artillery, and tank crews, paratroopers, and line of communication soldiers. The semi-automatic Carbine was issued with a 15-round magazine and featured a wooden stock. The M1A1 Carbine was made specifically for paratroopers and featured a folding stock and a leather cheek piece. Although the stock wasn’t as strong as it could be, the M1A1 Carbine provided a compact and easy-to-carry firearm for airborne units. Continue reading 30 Carbine Ammo at Ammo.com.