There has always been a driving force for a powerful yet manageable magnum handgun cartridge.

George Herter thought he invented the perfect cartridge way back in 1961.

Let’s take a close look at the long gone .401 Herters PowerMag cartridge.


The study of cartridges that have long fallen by the wayside for the quest of power and speed is an interesting hobby. Many great cartridges were quickly replaced by the newest and greatest of the day. Many times though, as the new-ness wears off, another newer miracle of modern weaponry comes along and takes the throne. Yes, sales drive new cartridge development as manufacturers fight to be number one in their perspective markets. Well, Herters decided a single action revolver chambered for a cartridge more powerful than the .357 Magnum but less recoil than the .44 Magnum was in order. Well, out of his catalog the claims went wild:

“The fabulous .401 Powermag…is the ideal large caliber revolver cartridge. Will kill any animal on the face of the earth, or shoot through the cylinder block of any automobile. It will flatten any human, no matter where you hit him…This is the finest big game or law enforcement revolver…With this revolver you can hunt deer, and all North American and African game…”. 

The revolver was made by Sauer & Sohn of Germany to be a copy of the famous Colt Single Action Revolver. The workmanship was said to be spectacular.

What were the actual numbers of this new medium to heavy hitter of the time? Well a cast lead bullet on top of a load of Unique powder was said to be the factory load I found during my research. Finding the actual charge weight of the factory loads has been also misleading. Also Herter’s did not actually manufacture the .401 Powermag cartridges but they contracted with J. P. Sauer & Sohn also to make them instead. What I did find is that 180 and 200 grain cast lead projectiles can be used. Also, it appears the .41 Remington Magnum cartridge and the Gun Control Act of 1968 (the end of mail order firearms) was enough to end the .401 PowerMag and plunge it into the category of long forgotten obsolete cartridges.

If you come across one of these old vintage throwbacks they are great revolvers by most accounts. You will certainly have to handload your own. I scoured through my vintage reloading books and I cannot find any data on loads at all. It appears most just skipped right over it as did the major gun publications of that time. Even a look through my “Professional Guide’s Manual” by George Herter, seventh edition, 1965, makes no mention of either the revolver or the cartridge. The first printing was in 1960, previous to the invention of the .401 PowerMag, so that could be the culprit for that vintage book.

Dig in and do your research if you want to make that ole hog leg roar again. Start lower in power, and work your way up. Be careful and always watch for signs of high pressure such as flattened primers after firing or firing pin area primer flow. No need to hotrod that old timer to have some fun.

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