.45 Armor Piercing bullet tech?

[Toast]

Yep, no AP handguns rounds allowed.

So is running M855 in a AR pistol a no-no? Or is it not because it's not AP, it's a "penetrator"?

[WTSGDYBBR]

principally used in a rifle . However a law is a law if it was chambered in a pistol what type of ammo does that make it and how would it stand in court ?

Is 5.56x45mm and 7.62x39mm principally used in handguns or rifles?
The answer explains why.