Read more: https://www.ammoland.com/2017/03/mannlicher-schoenauer-carbine/#ixzz6CxNuedRM

The designers of this classic rifle design were Ferdinand Mannlicher who was responsible for the action, and Otto Shoenauer, who conceived the removable, rotary magazine.
Its first appearance was at the 1900 World’s Fair, and the main emphasis was military sales.

The rifle action was a derivative of earlier Mannlicher military rifles, and it famously used a series of proprietary cartridges, most notably the 6.5X54mm M-S. The action featured twin-front opposed locking lugs a la “Mauser,” but also used a split rear bridge to allow an abutment that also had the bolt handle integrally-machined with it to act as a third “safety lug,” in the case of both front lugs failing from an over-pressure cartridge.
The most interesting part of the action though was Shoenauer’s magazine. Each rotary spool magazine was spring detachable from the action for cleaning. Each caliber had to have spools to match the portion of the case’s diameter to ensure proper function and feeding.
Every one is as smooth operating as if it was suspended on axles with ball-bearings.
The same could be said of the action’s operation. The beautiful close tolerances, heat-treatment of superior steel alloys, and the lack of drag against the bottom of the bolt body by a sprung magazine follower as in every other bolt-action rifle save the Norwegian / U.S. Krag-Jorgensen, means that it is the only bolt-action I am aware that it is capable of closing and locking an open bolt into battery by simply tilting the rifle toward the ground while keeping the trigger pulled.
The Greeks were the first and only military to adopt the M-S rifle as standard issue in 1903. After WWI, the factory built mostly hunting rifles, and none are more renowned than the 18.5” Carbines. There were various sub-variants with minor changes in 1903, 1905, 1908, 1920, 1924, 1950, 1952, and 1961, but none of the varied from the original design characteristics, mostly by cosmetic or dimensional changes to the wood stocking.
I am unaware of which specific M-S rifles famed Scottish hunter William Dalrymple Maitland Bell used to hunt/slaughter elephants prior to WWI. It is said that the vast majority of his over 1,000(!) elephant kills were with small bore rifles of 6.5mm through .303”, due to his study of elephant skull anatomy and placement of the shots into the brain from rear oblique angles.

Mannlicher-Schoenauer Carbine Patent Example Left side view. img gunsamerica.com auction sold 2014
The Mannlicher-Schoenauer Carbine is indeed a joy to hold and swing, much more in keeping with a shotgun than a rifle. My own M1952 was chambered in the then-new .308 Winchester and built in the late-1950s. It featured the then usual double-set trigger system found on most of the Carbines, whereby the rear trigger was used to set the front trigger to a pull weight of about 1.5lbs; far better than the stock, un-set pull of some eight creepy pounds! (a single-set trigger, or one with a proper 3lb release without the set mechanism is favored, though)
The major demerit of the M-S rifle or Carbine is the split-bridge action, making scope mounting both more difficult and higher in placement for clearance of the bolt handle. The M1961 rifles and carbines featured a Monte-Carlo comb and cheek rest design, along with the near obligatory era black plastic grip cap and fore-end tip with white plastic spacers, to help afford a proper cheek weld for accuracy consistency but made them ungainly compared to the former sleek shape of its forebears.
The only time this Carbine took big game in my hands was long ago on Santa Cruz Island off Oxnard, California, in the days before Bill Clinton via the Nature Conservancy made it into a National Wildlife Refuge, and nearly all the wild boars placed there as a food source by the Spanish in the 1600s were exterminated as a non-indigenous species. A running shot on a smaller sow at 75 yards with the set trigger and a Leupold Alaskan 3-power scope with one shot was all that was needed, just behind the right shoulder. A number of good dinners ensued.

Mannlicher Schoenauer Model 1903 Bolt Action Carbine with Scope **
Nowadays, these are valued collector’s items, yet there is a gentleman in Austria who apparently still manufactures these rifles and carbines, which Steyr-Mannlicher themselves discontinued in 1972, due to the expense of production.
The website, only in German, is found here: https://goo.gl/WFiYkB
The Mannlicher-Schoenauer Carbines are indeed beautifully-made arms before plastics and MIM dominated the firearms industry as it does so today.