.445 Super Magnum (using Sierra bullets)
Date: Feb 23 2021
During the 1970s there was growing interest in International Handgun Metallic Silhouette Association (IHMSA) competition, with the late Elgin Gates one of the major driving forces. The rather heavy steel targets consisted of chickens, pigs, turkeys and rams shot at distances of 50, 100, 150 and 200 meters respectively. This required a reasonably potent revolver load to provide enough down-range energy to reliably knock over targets, otherwise there was no score.
Gates is usually credited for the development of the “Super Mag” cartridges for IHMSA competitions, including the .357, .375 and .44 calibers; although he tested lengthened cases for .45, .50 and even .60 calibers. The .445 Super Mag is essentially a .44 Magnum case lengthened from 1.285 inches to 1.610 inches. It utilizes the same .429- to .430-inch bullets used in the .44 Magnum; however, with greatly increased powder capacity, it can push the same bullets around 300 fps faster.
In spite of the IHMSA currently having a rather limited following, Dan Wesson (distributed by CZ-USA) still offers guns chambered in .445 Super Mag. The test revolver, used here was one of the first guns produced by Dan Wesson Arms in Monson, Massachusetts and it proved to be accurate with select loads.
Loads were developed using 180-, 210-, and 220-grain Sierra bullets, but better overall accuracy was observed with 240- through 300-grain bullet weights.
Currently, .445 Super Mag cases are available factory direct from Starline Brass (800-280-6660). Select .44 Magnum carbide dies can be used to size cases, but not all. Redding .445 dies were used for load development.
While the accompanying data was fired using Federal 210 Large Rifle Primers, large pistol magnum primers such as the Federal 155 and CCI 350 can also be used.
Due to large case capacity reducing powder charges below the suggested “start” charges is not recommended, especially when loading spherical powders. A heavy roll crimp is suggested to prevent bullets from jumping crimp, but it also serves to help achieve reliable powder ignition.