And, you can put a bullet in the end of a pipe pretty easily. It doesn't have to be a good gun, after all.

If the quality of the gun was irrelevant to the effectiveness of the weapon, the military would be armed with homemade zipguns.

assassinations and such only require single uses.

different tools for different jobs.

We've been building decent guns for hundreds of years. You don't need computer controlled anything to make a working firearm for murder or self-defense.