Abstract: A firearm bore cleaning jag includes an elongated body defining an axis, with a first set of multiple fins and a second set of multiple fins positioned at first and second positions, respectively along the length of the body. Each of the fins has two opposed surfaces. Each of the opposed surfaces has an angle characteristic measured with respect to the axis. The opposed surfaces of each fin have different angle characteristics, such that one of the opposed surfaces is less acute than the other. The first set of multiple fins is arranged with their less acute surfaces facing in a first direction, and the second set of multiple fins are arranged with their less acute surfaces facing in a second direction opposite the first direction.