Minn: felon in possession of BB gun
A Minnesota court has upheld a felon-in-possesion prosecution based on posession of a BB gun.
State laws defining "firearms" fall into several classes:
1. Track the federal rule, basically a cartridge-loading arm.
2. Or expels projectiles by action of an explosive (nevermind that smokeless powder is hardly an explosive, legislatures don't know that much), or
3. Expels a projectile by means of an expanding gas (which would include BB guns).