A thumping wildcat that takes advantage of today's great bullets.
The M700 has been a popular action for building a rifle in .358 STA, a wildcat based on the 8mm Remington Magnum.
In a letter written to friend Townsend Whelen during early 1920s, Leslie Simpson-- one of the first Americans to become a professional hunter in Africa--opined that the hunting world needed a .35 caliber cartridge capable of pushing a 275-grain bullet along at a muzzle velocity of 2,500 fps.
Whelen was commanding officer of Frankford Arsenal at the time, and he relayed Simpson's idea to James V. Howe, who was foreman at the machine shop there. Howe came up with a .35 caliber cartridge on the .30-06 Springfield case and decided to name it the .35 Whelen in his boss's honor. It turned out to be a fine cartridge and an eventual favorite of gun writer Elmer Keith, but it was incapable of reaching the performance level desired by Leslie Simpson.
Howe later developed a cartridge that did meet Simpson's requirements, though. Called the .350 Griffin & Howe Magnum, the case was formed by necking down the full-length .375 Holland & Holland Magnum case to .35 caliber, decreasing body taper a bit for an increase in powder capacity and giving it a sharper shoulder angle.
I mention all of this to make a point: Most of the really good ideas in wildcats were used up many decades ago, and the majority of those introduced in the past few years pretty much duplicate something we already had.
A cartridge I introduced to hunters in 1992 and decided to call the .358 Shooting Times Alaskan is an example. Like the much older .350 G&H Magnum, it is on the full-length Holland & Holland belted case, but rather than necking down the .375 H&H I necked up the 8mm Remington Magnum case.
My case has less body taper and a sharper shoulder angle than the case designed by Howe back in the 1920s, so its powder capacity is slightly larger, but when both are loaded with bullets of the same weight there is not two cents' worth of practical difference in their performance on game. Some would say the .358 STA has a more modern look, but that doesn't make it kill a moose or elk any deader.
I will say my timing was better than Howe's. Back when the .350 G&H was introduced--and for well over half a century thereafter--all bullets of .35 caliber were intended for use in smaller cartridges. When loaded in larger cartridges and subjected to impact velocities higher than they were designed to handle, penetration on the larger game animals sometimes left a bit to be desired.
By the time I got around to designing the .358 STA, a variety of bullets capable of handling its velocities were available. And the options kept increasing in number. Anyone who wishes to load the .358 STA or any other big cartridge of its caliber won't go wrong with the 225- and 250-grain Nosler Partitions, Swift A-Frame bullets of those two weights and Barnes X-Bullets weighing from 180 to 250 grains. Barnes also offers a 250-grain solid.
Softer designs such as the Nosler 225-grain AccuBond and the 250-grain spitzers from Hornady and Speer are great choices for lung shots on game up to the size of elk, but at .358 STA impact velocities, tougher jobs call for tougher bullets.
One of the most accurate bullets I have tried in this cartridge is the Sierra 225-grain spitzer boattail. The .358 STA is far too much cartridge for deer, but if I should someday decide to use it to bring home the venison, the Sierra bullet is what I will use.
The first two rifles in .358 STA were built by Kenny Jarrett; I got the first one, and the second one went to Bob Nosler. Both were built on the Remington Model 700 action.
Bob used his rifle to bag the first Alaskan moose taken with the cartridge, and mine accounted for the first brown bear. We both used the same handload, 89.0 grains of H4350 behind the Nosler 250-grain Partition for close to 3,000 fps.
Chub Eastman, who worked for Nosler Bullets back in those days, used my rifle and a handload with the Nosler 225-grain Partition to take a nice elk.
The 5th and 6th editions of the Nosler data manuals have data, and Hodgdon's Annual Manual also has a few loads. The 2nd and 3rd editions of the Barnes manuals have quite a few loads for X-Bullets weighing 180, 200, 225 and 250 grains.
Best powders for maximum loads range from medium-slow burners such as H4350 and Reloder 19 to slower-burning powders such as H4831 and Reloder 22. I have used more H4350 with various bullet weights in the .358 STA than any other powder. I could get by with just it and perhaps Reloder 19 and IMR 4831.
Case-forming amounts to nothing more complicated than necking up the 8mm Remington Magnum case with a full-length resizing die equipped with a tapered expander button and fire-forming with 83.0 grains of H4350 with a 225-grain bullet or 79.0 grains of the same powder with a bullet weighing 250 grains.
Fire-forming rounds with the bullet seated out to firmly contact the rifling when chambered will increase case life by preventing excessive stretching just forward of the belt. Then seat the bullet short of contact with the rifling when loading those cases with full-throttle loads.
I'm thinking Leslie Simpson would love the .358 STA on lion, especially when it is loaded with some of today's incredibly good bullets.