Re: Handgun?
The issue isn't 3d printing a gun. It's 3d printing a very small restriction piece that turns the semi-auto back into an auto.
I don't think you grasp the supreme measure of just how wrong your statement is. A semi-auto firearm is one pull of the trigger, one shot. A semi-auto is never a converted full auto. You do not convert it back to a full auto firearm since it never was one.
There are many reasons why handguns are not full auto. The biggest is the one mentioned before. It's hard to keep a full auto rifle on target (Yes, I've fired full auto rifles in the military.) It is way much harder to keep small sub-machine guns on target like the Mac-10 and Uzi. The muzzle tends to go up very quickly unless you keep a hard downward pull on the forearm and the stock against your shoulder in the "pouch".
Secondly is heat. Full auto is constant firing. Emptying a full magazine heats up the receiver, bolt, and barrel to the point of almost not being able to hold it. Also could cause the spontaneous "cooking off" of rounds.
In the military you learn to fire no more than 6 rounds at a time. You learn to mentally say fire round of six, pause, fire round of six, pause. Then it's easier to control the up-sweep and not let the firearm heat up on you.
My experience with full auto firearms include the M-16, the M-4, the Thompson, the M-60, and even Madsens.
I'm ashamed of the Register for using