Mont. Code Ann. § 45-8-346
Possession of stolen firearm -- penalty
45-8-346 . Possession of stolen firearm -- penalty. (1) A person commits the offense of possession of a stolen firearm if the person purposely and knowingly receives, possesses, conceals, stores, barters, sells, or disposes of a stolen firearm.
(2) A person convicted of the offense of possession of a stolen firearm shall be imprisoned in the state prison for a term not to exceed 10 years.