The Caselman Air-Powered Machine Gun is an air gun designed to shoot .30 caliber slugs on full auto with approximately the same muzzle energy as a .32 ACP pistol. It was designed by Jeff Caselman in the 1980s as a way for any person to legally own a machine gun, one with enough power for self-defense. In 1990 Jeff sold the plans for the air machine gun for $19.99 and a instructional video on manufacturing it for $59.95. How long he sold these plans for, I don’t know. According to the late Mr. P A Luty, a master improvised gun maker himself, Jeff was never heard from again (although a video was published in 2011 showing a man named Jeff Caselman shooting a prototype air-powered shotgun). Luty took it upon himself to distribute the plans on his website. He called it “revolutionary in concept and design”.

Two weeks ago a reader, Mike, emailed us photos of a Caselman Air-Powered Machine Gun he built. It is a thing of beauty.

Mike has been running his at about 850 psi of air pressure, which results in 35 ft lbs of muzzle energy. The original plans specify it should be run at 3000 psi to give 125 ft lbs of muzzle energy.

Check out Mike’s blog. He make everything from violins to guns to homemade forges.

UPDATE: Mike sent in more photos …