Understanding Your Rifle
Mechanism
On this page you will find an explanation on how the Mauser 1889 works mechanically
Bolt
Unlike many of his later designs, the M1889 bolt uses a cock-on-close action. The sear catch would snag on the trigger sear, with the remaining forward motion being used to compress the firing pin spring.
The left side locking lug was split to allow the ejector to ride through it as the bolt travelled backwards and push the empty casing out to the side.
The bolt could then be locked in a safe position by turning the safety lever (often called flag safety due to its shape) to the right hand side, moving a piece of metal into the way of the striker, preventing it from moving forward and thus hitting the primer upon depression of the trigger sear.
The bolt is fairly simple in its design overall, but thanks to a non-separate bolt head it proved strong enough to last the nations that used it for a long time and was more than capable of withstanding even stronger munitions such as later updates to conical ("Spitzer") bullets or the German 8x57mm cartridge, which the M1889 was often rechambered to when captured by the German army.
One of the big improvements that would follow this model family was the implementation of a controlled feeding system. The M1889 had a simple push feed, where the extractor would slide over the rim only when the cartridge is fully inserted into the chamber. Beginning with the Model 1893, this would change to where the bolt fully controls the cartridge from the moment it picks it up from the magazine
Magazine
The M1889s magazine might be the most complicated part of the entire system, using flat springs and an arm linkage to move the follower upwards as the rounds are chambered.
The 1889 pattern and its subsequent models up to the Spanish Model 1892 were the only Mauser rifles to utilise a single stack magazine with the rounds sitting directly on top of one another, whereas the design changed to a staggered magazine with the cartridges sitting in an alternating left/right pattern with the Model 1893 family of Mauser rifles.
As mentioned before, despite the magazine being detachable by pressing the magazine release button on the inside of the trigger guard with the tip of a bullet, this was not to be done unless it was for cleaning or repairs.
Instead, the magazine feeding happened through the use of disposable clips, using a flat spring to keep the cartridges in place until they are stripped downwards using the thumb and into the magazine. Essential for this process was the bolt stop assembly, which also actted as the left hand side of the cartridge guide and kept pressure on the clip, holding it in place.
The clip guides would later become an integral part of the receiver bridge, with an update to the stripper clips negating the need to keep spring pressure on it to keep it secure while feeding.
Mauser's magazine patent from 1889 shows the relatively complicated follower assembly. Paired with the rimless 7.65x53mm cartridge, it was very modern at the time, but prone to damage and unwieldy during handling. The later staggered magazines allowed for a flush fit with the bottom the rifle, negating the mentioned drawbacks without a loss of capacity
Barrel Jacket
One of, if not the most distinctive feature of the M1889 is the barrel jacket, leading to its cannon-like look.
The barrel jacket was directly copied from the Commission Rifle 1888 and was only used on this one Mauser design.
The jacket had two main purposes:
Keeping the barrel insulated - The new smokeless cartridges and repeating rifles caused a stark increase in barrel temperatures due to increased heat generation from the friction generated by the faster projectiles, as well as an overall increase in the rate of fire thanks to reliable magazine systems.
As bayonet fighting was an integral part of a soldier's training, as well as an expectation on the battlefield, the jacket was supposed to allow the soldiers to handle the rifle effectively, even after several rounds caused the barrel to heat up.
Supporting the barrel on expansion - As mentioned before, the new heat levels that came with the use of smokeless propellants and magazines also resulted in metallurgic issues.
Whereas black powder single loading rifles had enough time between shots to let the barrel cool down again, it was now facing higher firing rates, causing increasing heat and thus steel expansion. The jacket allowed the barrel to expand without losing support, which would have resulted in accuracy issues.
The barrel jacket would disappear with Mauser's next model - the Ottoman M1890, which utilised a new patent of his in the form of a stepped barrel, which allowed for rather uniform heat expansion over the entire length. The handling issue was simply fixed with a handguard.
