Handloads for the .56-50 Spencer Centerfire
Date: Oct 22 2007
The original .56-50 Spencer cartridge was reported to have been designed by Springfield Armory around 1861 and soon thereafter offered in the Model 1865 Spencer lever-action carbine (as well as Remington, Sharps, Peabody and other arms). The case was a rimfire, loaded with a 350-grain bullet and driven with 45 grains of black powder. About 1920, ammunition was phased out, and it remains obsolete today.
Several years ago, Taylor’s & Company, Inc. announced a reproduction of the Spencer carbine, but chambered in a modern version of the .56-50 with centerfire ignition. The Italian firm Armi Sport is producing the rifle, which appears of reasonable quality and will serve reenactments and traditionalists well. It has taken sometime for the guns to actually make it into production but are now readily available.
As of this writing, there is only one company, TEN-X Ammunition (5650 Arrow Highway, Montclair CA 91763, www.tenxammo.com) producing factory fodder. Offerings include a 350-grain cast bullet at 1,279 fps (actual) and a black-powder load with the same bullet driven 986 fps (from a 20-inch barrel). I found these loads of high quality that offered low extreme spreads, accuracy and reliable functioning.
Handloading the .56-50 Spencer Centerfire
Before developing handloads for the new .56-50 Spencer centerfire, I had a number of questions that are pertinent to handloaders. The two most important are: To what pressure is the cartridge loaded or what is considered safe maximum? And what pressure levels is the action of the Armi Sport rifle capable of safely holding? These basic questions were asked of the importers (Taylor’s & Company and Cimarron F.A. Co.) and of the ammunition producer. As of this writing, no standard pressures have been established for either the rifle or factory ammunition.
In studying the design of the rifle, it is not especially strong, and handloaders should approach it with caution. The pressures generated by factory ammunition were determined and used as a guide in developing the accompanying handloads. It is suggested to keep pressures within 14,000 to 16,000 psi, with 18,000 psi being considered maximum. Pressures this low are difficult for the hobby handloader to determine using conventional methods such as measuring case head expansion, even when using sensitive calipers that measure as small as 0.0001 inch. So it is strongly suggested to use loads exactly as shown in the accompanying table. It should be noted, however, that loads approaching maximum usually gave the best accuracy.
There are challenges associated with developing handloads for this cartridge. Foremost is the large caliber and case capacity, combined with relatively low pressures. Many powders simply do not burn predictably or reliably at these lower pressure levels and can give erratic results. Others do not fill up enough of the case, leaving considerable air space, and as a result powder positioning becomes critical, which can adversely affect pressures, ignition, velocities and in several instances proved unsafe.