Quoted:
The ability to shoot fixed ammo is not determinative of a DD.
Destructive Devices are defined in Title 26 of the US Code(Internal Revenue Code). Under 26 USC 5845(f)(2) in addition to bombs and explosives, a DD also includes "any type of weapon by whatever name known which will, or which may be readily converted to, expel a projectile by the action of an explosive or other propellant, the barrel or barrels of which have a bore of more than one-half inch in diameter, except a shotgun or shotgun shell which the Secretary finds is generally recognized as particularly suitable for sporting purposes"
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Right you are, thanks. I confabulated the federal definition of DD with the CALIFORNIA one, to wit (from the OCR Penal Code):
12301. (a) The term "destructive device," as used in this chapter,
shall include any of the following weapons:
(1) Any projectile containing any explosive or incendiary material
or any other chemical substance, including, but not limited to, that
which is commonly known as tracer or incendiary ammunition, except
tracer ammunition manufactured for use in shotguns.
(2) Any bomb, grenade, explosive missile, or similar device or any
launching device therefor.
(3) Any weapon of a caliber greater than 0.60 caliber [b] which fires
fixed ammunition,[/b] [emphasis added] or any ammunition therefor, other than a shotgun
(smooth or rifled bore) conforming to the definition of a
"destructive device" found in subsection (b) of Section 179.11 of
Title 27 of the Code of Federal Regulations, shotgun ammunition
(single projectile or shot), antique rifle, or an antique cannon....
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If the feds ever took a strict interpretation, potato guns and a lot of other things would fall under that definition. "Other propellant" could include compressed air, spring power, etc.