Abstract: A tool for a firearm provides a member including a curved edge forming a comparison template adapted for comparison with feed slot elements of an ammunition magazine suitable for use with the firearm, for determining curvature corrections needed for the feed slot elements.

Abstract: The present invention is a magazine coupler for coupling first and second magazines together including a first and second plate each including a center leg and first and second outer legs which define first and second magazine recesses. The first and second guide rods each have a first end secured within the center leg of the first plate and a threaded second end received through corresponding aligned openings within the center leg of the second plate. The first and second securing members respectively received through the openings in the center leg of the second plate and engaged with the second ends of the guide rods to secure the first and second plates together in assembled relation. The first and second guide rods preventing rotation of the first and second plates relative to each other when secured in assembled relation.