Moon clip

A moon clip is a ring-shaped or star-shaped piece of metal designed to hold multiple cartridges together as a unit, for simultaneous insertion and extraction from a revolver cylinder.

The U.S. War Department asked Smith & Wesson and Colt to devise ways to use the M1911's .45 ACP rimless cartridge in their revolvers.

[2] Smith & Wesson invented and patented the half-moon clip, but at the request of the Army allowed Colt to also use the design free of charge in their own version of the M1917 revolver.

[4] Moon clips can be formed by stamped high-carbon steel, heat treated, and finished to prevent rust.

Jerry Miculek, an IPSC revolver shooter, has demonstrated the ability to fire six rounds from a Smith & Wesson Model 625 .45 ACP revolver, reload, and then fire six more rounds at the 6 in × 11 in (150 mm × 280 mm) A zone of an IPSC target at 15 ft (4.6 m) in 2.99 seconds.

Full and half moon clips loaded with .45 ACP and one Semiwadcutter .45 Auto Rim cartridge.
Smith & Wesson 1917 with .45 ACP moon clips and two auto rim cartridges
Rare Ruger Speed Six variant in 9mm Parabellum , which uses half-moon clips to chamber the rimless cartridges
Smith & Wesson Model 625 .45 ACP moon clips.