The liberator is the “hello world” of 3d printed guns. It is just barely functional enough to technically exist but practically isn’t of much use.

The barrel is so short and non existent that it basically does nothing except hold the (metal) cartridge in place. A liberator isn’t much different than simply holding a cartridge in a fixture and hitting it with a hammer.

In a conventional gun, the barrel serves to allow the projectile to build velocity and stabilize the trajectory by putting a spin on it. The liberator does neither, so the projectile will be moving quite slow and will be inaccurate.

And also, they do commonly explode, even on the first shot. It’s a gamble.

“Lethal velocities” doesn’t really mean much. A slingshot can propel a bullet at lethal velocities. And that would probably be a more suitable option for criminals as it would be more reliable and have more rapid fire capability.

Now it might be a viable one-shot gamble for a criminal in a place where guns are entire forbidden. But in those places, it is typically not easy to get a real .380 cartridge, so it doesn’t really change much. And in the US, there are much easier ways for criminals to get much better guns.