Schmidt Ruben Rifle
By R.K. Campbell

Among the more interesting idioms that have passed from the vernacular is the straight pull rifle. The Ross and the Mannlicher are well known but perhaps the best of the breed is the Schmidt Rubin K 31. The rifle was more expensive to procure than most rifles of comparable quality, such as the Mauser 98, but the performance of the K 31 was excellent. In both performance and in quality of manufacture the Schmidt Rubin fit the Swiss rifleman's ethic. Heralded as a nation of riflemen, the pragmatic Swiss realize that quality may make up for quantity. The Swiss maintain one of the best armed and equipped armies in Europe and their marksmanship training is legendary. All men from ages eighteen to sixty five are either reservists or in the Army. Weapons are secured in the home. This instant readiness and dedication are relied upon to keep the enemy away from the gate and marksmanship is stressed by the government.

The history of the straight pull Schmidt Rubin rifles began with Colonel Eduard Rubin and Colonel Rudolph Schmidt. Rubin directed a state munitions factory while Schmidt was a weapons officer. In conjunction with Schweizerische Industrie Gesellschaft (SIG), Schmidt and Rubin began developing a rifle designed to give Swiss troops every advantage. A new service cartridge was developed around 1883 and initial designs for the rifle were submitted in 1885. The straight pull made perfect sense as the potential for speed was greater than the bolt action rifles developed by most of the other European nations and quality manufacture, reliability and accuracy would be equal to any other type.

The Swiss straight pull apparently borrows nothing from the contemporary Mannlicher straight pull. The Schmidt Rubin rifle uses a bolt handle attached to an actuating rod. The actuating rod is the enabling feature of the design. There is a helical groove in the bolt sleeve that rotates to unlock opposing twin lugs from a recess in the receiver in the original design. To unlock the rifle the bolt is simply pulled to the rear. As the bolt is pulled to the rear, the empty cartridge case is ejected and the bolt is pressed forward to load a fresh case. Like most designs, the straight pull action of the Schmidt Rubin has certain trade offs. Initial extraction power was poor compared to the bolt action Mauser and the receiver had to be long to accommodate the straight pull action. On the other side of the coin, the receiver was practically debris proof. The introduction of smokeless powder and the fantastic advancement afforded by smokeless powder technology altered the development of the rifle. The 1889 modification of the rifle included the new smokeless 7.5x53.5mm cartridge. The resulting rifle was quite interesting although gawky in appearance by modern standards. The cartridge was loaded to typical ballistics of the day, with a heavy for the caliber 210 grain bullet propelled to about 1,970 fps. The powder combination used is best described as an early variant of smokeless powder referred to as semi-smokeless. The rifle went through progressive improvements, with the improvement centered primarily upon the locking lugs though the cocking ring in the rear of the action remained constant. This ring was pulled to the rear and turned to engage as a safety. Alternately, with care, the ring could be lowered to decock the rifle by pressing the trigger as the ring is lowered. For recreational shooters today the only sensible choice is to carry the rifle chamber empty and load it at the range. A modern feature of the rifle is a detachable box magazine that was retained throughout all modifications. Like most European armies, the Swiss adopted a carbine version and also a Kadet version for training.

The greatest news came in ammunition development. A 190 grain load at 2,050 fps was developed but was replaced with a more modern 174 grain Spitzer load clocking in at 2,640 fps. Realizing this new load was too powerful for older rifles, the Swiss changed the cartridge by creating the 7.5x55mm Swiss. The 1911 Schmidt Rubin was among the first of the truly modern Schmidt Rubin rifles and this rifle adopted the six shot magazine as a design feature. This slim-line magazine gave the rifle a more streamlined appearance. The Swiss carefully considered the service rifle and found it larger and heavier than needed. This was probably true of most service rifles immediately after World War One. The modified short rifle adopted by the Swiss was the K 31 carbine. A vital change came with the relocation of the locking lugs to the bolt head. The result of this arrangement is that the locking lugs butt into the receiver ring and this combination allows a more compact receiver. The Karbiner 31 is not only a more modern rifle than most military bolt actions, it is a very good looking rifle. Even though the rifle features a 25.7 inch long barrel it is scarcely longer than the previous carbine. The rifle is fairly heavy at almost nine pounds. Partly as a result of this weight the rifle is regarded as a light kicker although ballistically, the cartridge is comparable to the .308 Winchester. The rest of the story is history.

The Karbiner 31 was very successful and the rifle was the standard issue of the Swiss army until 1958. The K 31 has proven quite accurate due partly to the target grade bedding system. The raceway below the barrel is routed out for greater accuracy. Be certain all band screws are tight and that the tang screw is fully seated, for best accuracy. The bedding is rivaled perhaps only by the Mosin Nagant, another accurate rifle.

During the course of manufacture there were both target and competition versions as well as sniper versions. The rifle illustrated is a joy to handle and fire. The rifle is a later model K 31 with a walnut stock, while many were of less expensive wood. The rifle is very smooth in operation. Everything about the rifle impresses.

A firing test of the rifle was held up for a want of ammunition. During a protracted ammunition drought, all ammunition was short in supply and 7.5 Swiss was not a priority among dealers. We were able to obtain a few rounds of European ammunition that were recreational grade at best, reliable but not exhibiting the accuracy potential of the rifle. Thankfully, Graf and Sons has partnered with Hornady ammunition to offer custom grade loads at an affordable price. When bench resting the rifle, the fixed iron sights proved to be excellent examples of the breed with a clear-cut sight picture. This author has never found a clearer sight picture than this one. Working with the full metal jacketed loads on several occasions, printing three shot, three-inch 100 yard groups were easily obtainable. The bolt proved easily manipulated and ejection was positive. After a few magazines of these loads we let the rifle's barrel cool and addressed the Hornady loads. The first group was fired with the 165 grain Boat Tail Soft Point and was rewarded with a singular 1.5 inch three shot group. Following that, the 168 grain A Max load was used firing three shot groups, relaxing between shots and allowing the barrel to cool for a few seconds with the bolt open. While one group went into a pleasing 1.25 inch group, the average for the three groups was 1.65 inches. The sights were good and the trigger action aided in accuracy, breaking at a very clean 3 pounds even.

This author's observations conclude that this is an accurate rifle. It is easy to carry as the balance is in the receiver and tang. While the receiver design may be resistant to dirt and debris, some of the exposed mechanism would be another matter. The 7.5mm cartridge is on a par with the .308 Winchester or 7.62mm NATO, accurate, mild to fire and effective. Overall, the Schmidt Rubin is an impressive rifle that is a welcome addition to any collection.

This article first appeared in Small Arms Review V14N11 (August 2011)
and was posted online on November 1, 2011


Comments have not been generated for this article.