[Calvin Locke]

The Thompson was mostly machined, and expensive by the war. $200 sticks in my mind. For the war, the drum magazine capability was eliminated.

One show said that after each British Commando raid on Norway, the armorers come in to collect the Thompsons ahead of the medical personnel.

I think the only machined part in the M3 "grease gun" was the bolt. It was also field convertible to fire the German 9mm MP40 ammo.

Back in the day, early 1970s, my (8th grade?) class took a tour of the FBI building in DC. An agent fired off a drum on the Thompson, and handed out the spent casings as souvenirs. Yes, they had an enclosed/soundproofed/bullet proof glassed firing range in the building to show off.

[Forward the Light Brigade]

Zip guns are easy to make-—anyone can do it with a little bit of creativity. Same with a very lethal Crossbow or rubber band powered slingshot gun. Black powder also can be used to make a rather large single shot weapon. History can be very informative about such things.