The Karabiner 98 Kurz (often abbreviated Kar98k, K98, or K98k) was a bolt action rifle chambered for the 7.92×57mm Mauser cartridge that was adopted as the standard service rifle in 1935 by the German Wehrmacht.
It was one of the final developments in the long line of Mauser military rifles.
Although supplemented by semi- and fully automatic rifles during World War II, it remained the primary German service rifle until the end of World War II in 1945.
The Karabiner 98k was derived from earlier rifles, namely the Mauser Standardmodell and the Karabiner 98b, which in turn had both been developed from the Gewehr 98. Since the Karabiner 98k rifle was shorter than the earlier Karabiner 98b (the 98b was a carbine in name only, a version of Gewehr 98 long rifle with upgraded sights), it was given the designation Karabiner 98 Kurz, meaning "Carbine 98 Short". Just like its predecessor, the rifle was noted for its reliability, great accuracy and an effective range of up to 500 metres (550 yd) with iron sights and 1,000 metres (1,090 yd) with an 8× telescopic sight.
The Karabiner 98k was a controlled-feed bolt-action rifle based on the Mauser M 98 system. It could be loaded with five rounds of 7.92×57mm Mauser ammunition from a stripper clip, loaded into an internal magazine. Alternately, cartridges could be loaded singly into the magazine by hand. The straight bolt handle found on the Gewehr 98 bolt was replaced by a turned-down bolt handle on the Karabiner 98k.
This change made it easier to rapidly operate the bolt, reduced the amount the handle projected beyond the receiver, and enabled mounting of aiming optics directly above the receiver on the Karabiner 98k.
Each rifle was furnished with a short length of cleaning rod, fitted through the bayonet stud. The joined rods from 3 rifles provided one full-length cleaning rod.
The metal parts of the rifle were blued, a process in which steel is partially protected against rust by a layer of magnetite (Fe3O4).
Such a thin black oxide layer provides minimal protection against rust or corrosion, unless also treated with a water-displacing oil to reduce wetting and galvanic corrosion.