Q: I have a question about the .30 M1 Carbine cartridge. I have a friend who was stationed at Dutch Harbor with the Navy in the 1970s, and he said he had a belt that had .30 Carbine cartridges in it and his job was to take them out of the belt. I don’t know if the belt was cloth or metal. I was at a cartridge show and picked up a .30 Carbine cartridge that was pointed like a .30-cal. rifle cartridge. It had a “45” stamp on it, and it was made from steel. It was too long to fit in the M1 carbine magazine. Did the military ever experiment with a light machine gun using the .30 Carbine cartridge?
A: Thanks for your recent letter. There is absolutely no evidence that the American military did any experimentation with a belt-fed (or any other type) light machine gun chambered for the .30 Carbine cartridge. In any event, the .30 M1 Carbine cartridge would be much too anemic for use in a light machine gun.
I strongly suspect the carbine cartridge you saw with the pointed-tip bullet and longer-than-normal length was an “M18” high-pressure proof cartridge. These were used to “proof test” carbines at the factory and were singly loaded into the gun, thus did not feed through the magazine so the longer length was not an issue. These were made in both brass and tinned case configurations.