The Swiss K31
A bit of history on the last—and possibly best—bolt-action designed for military use
So, as I said, I ran across a Swiss K31 straight-pull military rifle, which I had never seen before, and since I’ve seen just about every gun before, it was intriguing, so I did some research, and it became even more intriguing.
The K31 was probably the last bolt-action rifle to be issued to an army. It was designed in 1930 at the Swiss Arsenal in Bern, and the first test guns were given to soldiers in 1931. It was a replacement for the elderly, cumbersome Schmidt-Rubin straight pull, and is sometimes referred to as the Schmidt-Rubin K31, but that is erroneous, and neither of those gentlemen had anything to do with it, both being dead at the time.
The K31 was a vast improvement over the old Schmidt-Rubin. K stands for “karabiner,” and although it looks like a carbine alongside its predecessor, its barrel is actually 26 inches long, which is 2 inches longer than the Springfield 03. Its receiver is shorter, and stronger than that of the Schmidt-Rubin, and the rifle weighs just under 9 pounds, unloaded, which for the time was relatively light.
The barrel was free-floating, and the trigger was excellent for a military arm. The K31 was issued with a single detachable six-round magazine, and soldiers were expected to reload it from stripper clips.
The cartridge for which the K31 was chambered was designated the GP11, or 7.5×55. It was a highly advanced round that was designed to work either through rifles or machine guns. It fired a 174-grain bullet at 2560 fps, which makes it the identical twin of the U.S. M118 7.62mm sniper round, except that the current version of the M118 appeared in 1993, and causes you to wonder if maybe we shouldn’t hire the Swiss to design our weapons.
The new rifle was an immediate hit, and came into general issue in 1933. It would keep its place until 1958, when it was replaced by a powerful semi-auto assault rifle designated the PE-57.
Being a straight pull, the K31 was much faster to operate than a conventional bolt action. You hauled back on a barrel-shaped handle on the right side of the action, slammed it forward, and you were all ready to shoot whoever was dumb enough to invade Switzerland. The safety was a ring at the rear of the bolt, and it functioned both as a safety and as a cocker/decocker. The action could be disassembled in seconds, and without tools.
The Swiss have always placed a premium on precise shooting, and the K31 was true to that tradition. Its effective range is 540 yards, and it was/is exceptionally accurate for an issue military rifle of that period or this. I understand that it’s common for K31s to shoot minute-of-angle groups with iron sights and standard military ammo. I can’t think of anything else that will match it.
K31 stocks were made of either walnut or beech, and beneath their buttplates sometimes lurks a surprise for the person who comes to own one. The Swiss had a practice of slipping ID tags there. These little pieces of paper contained the name and birth date of the soldier who had been issued the rifle, his unit, and the town in which he lived.
The K31 carries with it two great ironies: It was not only the last military bolt-action to be designed, but it was quite likely the best. I can’t think of anything better, and probably the only rifle that could match it in World War II was the M1 Garand. Second, and even stranger, it’s quite probable that the K31 never fired a shot in anger. The Swiss remained neutral through World War II, as even Der Adolf was not crazy enough to invade them.
Because the Swiss have a comparatively small army, only 528,000 were made, which is piddling for a military rifle. The United States produced 5.5 million M1 rifles during World War II.
Today, the sterling qualities of the K31 are finally being recognized. You can find one fairly easily. A rifle in good condition will run around $400. Something really nice will go for twice that, and a veritable jewel can cost well over $1,000. This is fair. The K31 is built to a standard that you no longer see in military small arms, or in much of anything else for that matter.
It’s an eminently useful rifle that’s finally getting the recognition it deserves. And if you find an ID tag under the buttplate, leave it. The soldier who put it there would want it that way.