.43 Mauser (11.15x60R) (Lee Precision Data)

.43 Mauser (11.15×60R) (Lee Precision Data)

The .43 Mauser, designated commercially as the 11.15×60R, dates from the 1870s and was originally developed for the Mauser Model 1871 rifle — Germany’s first official smokeless black powder service cartridge. While largely obsolete in modern mainstream shooting, Lee Precision includes reloading data for this classic cartridge in its die listings and manuals, offering a practical path for shooters, collectors, and black-powder cartridge enthusiasts who wish to handload this historical round.

According to Lee Precision’s published information, the 11.15×60R (also marketed as .43 Mauser) uses a large rimmed case designed around the heavy lead bullets that were typical in late-19th-century ammunition. Lee’s data specifies dies and shell holders suited to reforming brass and resizing cases, and lists bullet diameters around .446–.448" — matching the bore specifications of most surviving vintage rifles chambered for this caliber.

Lee’s reloading data emphasizes safety and conservative use of black powder or equivalent modern substitutes in lieu of original charges. Traditional black powder charges for the .43 Mauser historically ranged from roughly 70 gr to 82 gr of FFg or FFFg, producing muzzle velocities in the neighborhood of 1,350–1,450 fps when fired through 30- to 32-inch barrels commonly found on Model 1871 and similar rifles. Lee’s recommendations for modern handloaders include starting with the lower end of traditional charges and working up cautiously while watching for pressure signs — particularly on older military surplus rifles where metallurgy and chamber condition may vary widely.

Key Lee Precision considerations for the 11.15×60R include careful attention to bore diameter and slug measurement, proper trimming and deburring of case mouths, uniform neck tension, and the use of large rifle primers. While Lee’s dies support resizing and bullet seating, many handloaders choose to cast their own lead bullets or work with specialty bullet manufacturers to match the heavy, soft lead rounds that replicate original ballistics and maintain safe operating pressures in antique actions.

Modern smokeless substitutes such as IMR 4198 or SR-4759 can be used at reduced charges to approximate the performance of traditional black powder loads — but Lee’s data underscores that this should only be done by experienced reloaders with thorough knowledge of pressure behavior, barrel condition, and historical black-powder cartridge dynamics. Because most antique rifles in 11.15×60R were designed around black powder pressure curves, Lee’s data advocates slower development and incremental load testing with a chronograph and detailed logging.

While not a cartridge for casual plinking or high-volume shooting, the .43 Mauser (11.15×60R) remains a fascinating historical caliber — and Lee Precision’s inclusion of reloading data in its manuals reflects an enduring interest among collectors and dedicated long-arm shooters in preserving and responsibly using these vintage rifles.

Source: Lee Precision reloading data listings and manuals (11.15×60R / .43 Mauser)