Like Taking Money from a Baby

Something dislodged from the recesses of my imagination:

What would happen if you robbed a bank with a BB gun? Walk up to the counter with one of those pump-action air rifles and clickety clack it as the urgency in your voice grew. Your eyes focus as the pumping gets harder, the air more condensed, the pellet ready to fly with enough velocity to penetrate a layer or two of skin.

Could you be arrested for armed robbery? Is a BB gun considered a toy or a weapon?

If that's not your thing, how about an archery set? Keep a dozen arrows in your quiver, lest the security guard think you're not committed to the job.

I suppose, from a merely technical perspective, a Swiss Army Knife could be declared a weapon. It's as deadly as a switchblade (plus you can uncork a bottle or pick the tiny sprig of broccoli from your teeth with the former). So is it armed robbery only if the weapon is visible? Would a bulging pocket qualify, or would your defense hinge on you just being happy to see the teller?

I dunno. Maybe I'm overthinking this. But if you construct a gang with wristrockets, BB-guns, and an Indian burn specialist to torture the manager into providing the combination for the vault...