(1)Subject to subsection (2) below, it is an offence to shorten to a length less than 24 inches the barrel of any smooth-bore gun to which section 1 of the principal Act applies other than one which has a barrel with a bore exceeding 2 inches in diameter; and that offence shall be punishable—
(a)on summary conviction, with imprisonment for a term not exceeding six months or a fine not exceeding the statutory maximum or both;
(b)on indictment, with imprisonment for a term not exceeding five years or a fine or both.
(2)It is not an offence under this section for a registered firearms dealer to shorten the barrel of a gun for the sole purpose of replacing a defective part of the barrel so as to produce a barrel not less than 24 inches in length.