The Good & Bad of The Short Magnums: Super Shorts & Fat Cartridges

This segment covers the good and bad of the popular short magnums. We take the extra step and put extra-high-velocity cartridges to the test! Stay tuned for more on the short magnums!

muley buck

The Winchester Model 70 chambered in 7mm WSM worked well for Tom’s wife, Donna, in taking this fine muley buck.

Much like a coyote drawn to a rabbit distress call, for those of us that love to shoot, the lure of trying new shooting related products is an urge we simply can’t resist. Inherently, hunters and shooters are forward in their thinking and as such they often are excited at the prospects of being able to improve their performance through the use of innovative new products. So when Remington and Winchester began ushering in their new lines of short magnum cartridges I, like many other shooters, was anxious to have a closer look. Many of these cartridges promised magnum level performance, but in a cartridge case that was short enough to be used in a short action firearm.

Winchester simply labeled their new line the Winchester Short Magnums (WSM) and Remington chose to call theirs the Remington Short Action Ultra Magnums (RSAUM or SAUM). Before long, stiff competition developed between Winchester and Remington for this marketplace. In reality, however, when a close comparison is made between the Winchester brand cartridges and the corresponding Remington versions, there is little difference either visually or in their performance. But while they might appear similar, the WSM and RSAUM cartridges are not interchangeable. At all.

It wasn’t long after these cartridges materialize that some of the hype started to fade from the scene. And, as I write this article, I have learned that while Remington is still manufacturing ammunition in their RSAUM calibers, they are no longer chambering any of their Remington brand rifles for those RSAUM cartridges. What went wrong…and was there much right with the concept initially?



Adding a bit more confusion to the mix, Winchester also came out with a line of cartridges styled similar to their WSM line, but which they called the Winchester Super Short Magnums (WSSM). While characteristically very similar in general appearance to the WSM cartridges, rather than primarily competing with the standard-length magnum cartridges, as the WSM & RSAUM were intended to do, the WSSMs offered an alternative to some of the non-magnum cartridges like the .223 Remington, .243 Winchester, and the various .25s. In most cases, but not all, the WSSMs provided an increase in velocities over the older traditional rounds.

Australian wild boar

Tom’s 7mm WSM proved to be up to the challenge on Australian wild boar.

But aside from any potential increases in velocities, the companies claimed that the larger case diameters of the WSSM, RSAUM and WSM cartridges produced another advantage: powder efficiency. The theory was that increasing the cross-section diameter of the cases would result in a more efficient burn of the powder charge. While I’m not totally convinced that there was any appreciable benefit from this, it was the belief by the manufacturers that this would be beneficial and result in improving the cartridge performance.



From the start, the sales of the Winchester Short Magnums seemed to outdistance the Remington Short Action Ultra Mags. But, while some of the WSMs seem to continue to have a faithful following, the WSSMs haven’t done so well. As such, I believe it is likely that in the future that many of these will follow the 5mm Remington Magnum to their doom. Whether or not any of the WSMs survive in the long run has yet to be determined. My best prediction would be that if any do last the test of time, it will likely be the .300 WSM, and possibly the .270 WSM, .325 WSM, and the 7mm WSM. Personally, I’m not convinced that there is a significant amount of benefit from these cartridges, but I felt I had to at least try one of these cartridges out for myself…so I chose the 7mm WSM.


Stay tuned to hear all about the 7mm WSM experience! 


Story & Photos by Thomas C. Tabor


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