Tightening Up The .30 Carbine

United States carbine, Caliber .30, M1 accuracy is pretty dismal as issued but can be improved.

By RK Campbell

If there has ever been a tribute to American manufacturing ability it is the .30 US M1 Carbine. Over six and one half million carbines were manufactured and they are generally reliable and trouble free. The single most common complaint was poor wound potential, but this occurred when the rifle was pushed beyond its role as a PDW (Personal Defense Weapon), a term not coined in 1942 when the rifle entered service. This carbine is a very neat little rifle. It has a traditional look with the exposed barrel and cut down stock of a carbine in Krag and Springfield style, however, the M1 Carbine uses a low power rifle cartridge rather than the same round as the service rifle. Tank crewmen, truck drivers, ammo bearers and officers had previously been armed with a handgun. The idea was to give the troops a service weapon superior to the handgun but not as heavy and difficult to manage as the M1 Garand. Winchester succeeded admirably with the .30 carbine as it remains popular for personal defense, some forms of competition in certain side matches and for recreation. While normal repairs sometimes center on a lack of lubrication and a need for cleaning, some shooters will wish to have the rifle accurized.


  1. Just bought Iverjohnson M1 30 cal carbine used. Bolt slide hangs up occasionaly when pulling it back manually. I broke it down, cleaned and lubued everything but still hangs up. It fires perfectly. Is the problem I’m having with my used Iverjohnson 30 cal carbine a common one, and if so what is the fix? Is this a sign of a worn bolt or other parts?

    • Author RK Campbell responds.

      Without having the firearm on hand, here is my best guess. Replace the original recoil spring with one from Wolff Gunsprings (gunsprings.com, 610/359-9600.) Do not use the extra power spring. Check the gas piston to be certain it is only moving about a quarter inch.

      It’s also possible the extractor and ejector are sticking, not the bolt. If you buy a new bolt with new extractor and ejector, that might fix it. Order of priority would be to try the recoil spring, then gas piston, and then the extractor and ejector.

Leave a Reply

Fill in your details below or click an icon to log in:

WordPress.com Logo

You are commenting using your WordPress.com account. Log Out /  Change )

Twitter picture

You are commenting using your Twitter account. Log Out /  Change )

Facebook photo

You are commenting using your Facebook account. Log Out /  Change )

Connecting to %s