(1) Subject to subsection (2), a person other than a firearm dealer shall not—
(a) shorten the barrel of a shot gun to a length of less than 18 inches;
(b) convert into a firearm anything which is not a firearm;
(c) convert into a restricted weapon anything which is not a restricted weapon; or
(d) convert into a prohibited weapon anything which is not a prohibited weapon.
(2) A firearm dealer shall not, without the prior written approval of the appropriate authority, do any of the things referred to in subsection (1).
(3) A person who contravenes this section commits an offence and is liable on summary conviction to imprisonment for a term of not less than 5 years or on conviction on indictment to imprisonment for a term of not less than 15 years.