40 EIMER COLT

One of the first shooters and wildcatters that began experimenting with .40cal. cartridges was “Pop” Eimer, a Joplin Missouri gunsmith who, in 1924 started cutting down 401 Winchester Self Loading cases to 1,25” for use in a Colt Single-Action Army revolver that was modified with a .403” .38-40 WCF barrel and a custom cylinder. This cartridge became known as the .40 Eimer Colt, or .40 Eimer Special. Like many wildcatting ideas in the early years, the biggest problem was that the correct powders were not yet developed for what these pioneers set out to achieve, but with the existing faster burning powder (9 grains of Du Pont Pistol No.3) and vintage quality steel he achieved better ballistics and accuracy than the 38-40 WCF without any noticeable increase in recoil.