The 38 Long (Caliber .38 Revolver, Ball) was developed in 1875 by Colt and is essentially a centerfire version of the .38 Long rimfire, originally developed by UMC in late 1873 or early 1874 for the Navy to use in their Colt M 1851 and 1861 revolvers that were converted by Colt to centerfire. The US Navy (Colt Navy) cartridge was a rimmed case with outside lubricated bullet and a case length of approx. 0.87”. It differs from the US Army (Long Colt) that had an inside lubricated bullet and a case length of approx. 1.03”, although for both the over-all length is basically the same. The outside lubricated version was not used for a very long time and has therefore only seen limited production for the military. It was both a commercial and military round at the same time, although it started life as a commercial cartridge. All headstamped loadings by Frankford Arsenal have the later, inside lubricated bullet. (Erlmeier, Brandt Ref. 359)

1st specimen is an early UMC loading. The 2nd specimen is an early US Cartridge Co. loading. The third is an early Farington Primed load also by the US Cartridge Co. The .38 Colt Navy headstamp was also by the US Cartridge Co.