Free: Contests & Raffles.
Bolt action, pump action, or semi auto. If the barrel is less than 16" and the over all length of the firearm is less than 26". You then fall into the pistol or short barrel weapons category. Once that happens, you have an entirely two different sets of laws. Which is no butt stock and no second vertical hand grip. For a pistol. In realty, it is stupid to think a second grip makes a bit of difference as to how the weapon preforms. Or how the shooter holds it or what ever reason the ATF has decided. But it is the ATF ruling. Which means without due process. It becomes an automatic law.