30 Carbine- The Little Cartridge That Could

The controversial M1 carbine was an enlightened development when introduced. Just strong enough to do the job, it had far more effective range than open bolt submachine guns, was lighter than either SMGs or the M1 Garand, and carried a lot more ammunition for the same weight. It’s no surprise that it wound up on the shoulders of not just support personnel, but also Marine raiders and allied Asian troops. The carbine itself was less controversial than its cartridge, maligned frequently but used even more frequently.

Compared to its Combloc counterpart, 7.62x25mm Tokarev, the M1 carbine bullet was about 30% faster and 30% heavier. Relative to American submachine guns, M1 won all-around. A complete 30 carbine cartridge weighs 195 grains, just under 2.8 pounds per 100. 45ACP was heavier at 3.3 pounds, and limited to a far shorter effective range. There’s a reason why the issue of carbines continued through the Vietnam war, while M3A1 Grease Gun was relegated to tank crews where length was the critical consideration. Thompson M1 with a 20-round box magazine was twice the weight of the slim carbine. For all the complaints about 30 carbine under-penetrating, I don’t recall its bullets being stopped by packed wet snow or a medium watermelon, both of which captured 45ACP ball. In fact, carbine gel tests resulted in bullets punching through two 16 inch blocks set up end to end, and escaping into the backstop. In the words of a Korean War vet: “I can’t tell you how effective 30 carbine was — everyone I shot with it promptly curled up and died, and were unavailable to comment.” Slightly less effective than 7.92×33 STG44 round, 30 carbine had the virtue of coming out of a a sub-6lb weapon (loaded) rather than an STG44, twice as heavy loaded. Low recoil and decent accuracy also lend M1 carbine to night operations with early infrared scopes.

In modern non-military defensive use, the standard 110-grain FMJ cartridge is a bit of a liability due to excessive penetration through walls or people. It’s great for range use, but expanding bullets make better use of the available kinetic energy. Of the many available defensive loads, only some can be recommended due to reliability concerns with the others. For example, a fairly effective Hornady Critical Defense load is too long to fit some M1 magazines without the red plastic tip catching on the front wall. Remington soft point bullets with exposed lead can drag on the magazine wall, again reducing feed reliability. All-copper Maker Bullet 110-grain hollow point used by Steinel is short enough to feed, and has a modestly sized opening to avoid snagging on the feed ramp. It matches FMJ ballistics closely, so that the same point of aim works with practice and defense rounds. Converting kinetic energy to projectile deformation and making a larger wound channel keeps the bullet from over penetrating. Since the greatest contributor to over penetration is missing the target outright, we recommend equipping your M1 carbine with a red dot sight on a railed hanguard, such as Ultimak.

While over 30 rifles and handguns have been designed around the 30 carbine cartridge, the original US M1 and M2 (to which most M1s have been updated) remain the most popular. In fact, the sheer number of surplused carbines led to a change in NFA rules in favor of the M1 owners. What a contrast to the current government policy! Across the Atlantic, Israel still issues M1 carbines to volunteer school guards to protect students on field trips. Today, with improved sights and ammunition, M1 carbines are more potent than ever. In private hands, they are far more likely to be used for short-range defense than as a battle rifle substitute at hundreds of yards, so the initial complaints about them being underpowered are hardly valid. As numerous deer harvested with them every year indicate, the platform is plenty sufficient to drop a large mammal in its tracks. Careful ammunition selection is key, same as with handguns.