Under 26 USC 5861 (d), which of the following is NOT considered a regulated firearm?

The definition of a regulated firearm under 26 USC 5861 (d) includes certain categories such as short barreled shotguns and smooth bore pistols, which are specifically mentioned as subject to regulation due to their design and intended purpose. A muffler or silencer also falls under regulated items because they are considered devices associated with firearms intended to suppress sound.

In contrast, a standard hunting rifle does not meet the criteria for regulation under this statute. Hunting rifles are typically designed for sporting and recreational use and are not classified under the same restrictions as items like short barreled shotguns or silencers. This distinction is crucial, as it reflects a broader legislative intent to govern firearms that pose particular risks beyond general hunting or sporting activities. These regulations aim to manage items that might be easily concealable or used for purposes other than lawful hunting or shooting sports.