Abstract: A perforating gun is designed to have explosive charges spirally disposed around its circumference in accordance with a displacement angle defined as (m/p)(360.degree.), where p is a whole number greater than 4 and m is a whole number greater than 1 but less than (p-1) and where m/p is an irreducible fraction. A U, or horseshoe, shaped retainer clip holds individual charges in respective holes and cavities of an outer carrier tube and an inner carrier tube to prevent horizontal or transverse movement of each charge and thereby hold it in contact with an axially extending detonator cord.