I've been saying the same thing for a long time
But at the end of the day it will still, basically, be a gun. Lumps of metal driven by expanding gas will fly out of the end at high speed, and make holes in things or people which they hit.
Again, a firearm is a simple device. It is a tube, enclosed at one end with a projectile that is expelled out the other by means of pressure. You can use PVC for the tube, a sack of nails for the projectile, and lighter fluid for the propellant and create a firearm.
If you aim said creation at a water jug to watch it explode, it's harmless - aim it at a living thing, it is then lethal. Either way, it's a human who determines the lethality of a firearm, not the size of the projectile, not the plastic grips, not the folding stock.
Nobody tell Delaware's Toughest Liberal this, he still thinks the gun has a mind of its own.