Knee joint closure

from Wikipedia, the free encyclopedia

The knee joint lock is a type of lock for firearms. It was used for repeating pistols , repeating rifles , self-loading pistols , self-loading rifles, as well as machine pistols and machine guns .

Automatic firearms with knee-joint lock are recoil loaders , they belong to the self-loading weapons with a short sliding back barrel.

use

Repeating weapons

Knee joint lock on Volcanic weapons, the Henry and the Winchester Mod 66, 73 (picture) and 76

Knee joint locks have been used in manually repeating weapons since the 19th century. The first weapons with a knee joint lock were Volcanic pistols and rifles developed around 1851 by Horace Smith, who later became Daniel Wesson's partner ( Smith & Wesson ) , the Henry rifle in 1860 and the Winchester model in 1866, 1873 and 1876, and the Colt-Burgess Rifle .

A knee joint lock that swings out to the side was developed by the Suhler Jagdwaffenwerk in the GDR for the model 628 biathlon rifle . The Soviet-Russian manufacturer Baikal also used lateral knee-joint locks for its models 7-2 , 7-3 and 7-4 . Also in Suhl in 1979, the 626 model for top biathlon athletes was developed, which was based on the Henry knee joint system. Instead of the swiveling trigger guard, this rifle was repeated using the moveable pistol grip on the stock, so that the hand can remain on the grip during reloading.

Automatic weapons

Schematic representation of the knee joint lock of a pistol 08

The first automatic weapon with a knee joint lock was the Maxim machine gun developed by Hiram Maxim , the principle of which was patented in 1885 (patent no. 14047). The knee joint lock was used in numerous machine gun models derived from Maxim's design and was also used in self-loading pistols such as the Borchardt pistol and the pistol 08 . It is practically no longer used in modern weapons.

function

System Maxim, Luger

The knee joint is initially hyperextended downwards (see illustration), the lock is locked. When the shot is fired, the barrel and slide are accelerated backwards by the recoil . After a certain distance, the knee joint is unlocked by a control cam attached to the fixed part of the weapon. The distance is dimensioned in such a way that the gas pressure and the recoil force generated by it are largely reduced. The unlocked lock runs back due to the principle of inertia . The empty cartridge case is ejected. Then the slide and barrel are pushed forward again by springs. During the advance, a new cartridge is fed from the magazine or the cartridge belt into the chamber .

Schwarzlose

Function of the delayed mass closure of the MG Schwarzlose

A variant of the knee joint lock is used in the Schwarzlose machine gun . This MG has a fixed barrel and a delayed mass lock . When the shot is fired, the return movement of the slide is delayed by a nearly closed knee joint; this is hinged to the front of the housing and to the rear of the bolt head. A lever attached to the rear of the knee joint transfers the movement in an accelerated manner to the rear component of the lock, which is loaded by the closing spring and which also carries the firing pin. On the one hand, this contributes to the delay, on the other hand, a separate spring for the ignition can be dispensed with.

Pedersen knee joint closure, function

Pedersen

The semi-automatic American Pedersen rifle, like the Schwarzlose machine gun, has a fixed barrel and a delayed locking mechanism with a knee joint that is not fully extended. The contact surfaces between the lock and the legs of the knee joint are calculated in such a way that they roll off each other and thus significantly delay the opening of the lock. The rifle took part in the tests carried out by the American army from 1920 to 1930, but was not accepted because it fired a weak cartridge, the .276 Pedersen , which also had to be waxed or greased to ensure its function. The winner was the M1 Garand , a gas pressure charger.

System Furrer

Function of the knee joint locking system Furrer

All series fire and self-loading long guns manufactured in the Bern Waffenfabrik between 1925 and 1945 were based on the knee joint lock developed by Colonel Adolf Furrer , the director of the Bern Waffenfabrik at the time . The first weapon made on this principle was the Lmg 25 . Then all of them, from the 9 mm submachine gun to the 24 mm tank rifle 41 to the 34 mm anti-aircraft cannon , were built according to the same Furrer locking principle. The Furrer knee joint lock system is not bent by a control curve, but by a support joint attached to the extension of the rear joint. The support joint articulated on the rear arm of the knee joint is pivotably connected to the fixed part of the weapon. It stands approximately at right angles to the rest of the lock, supports the extension of the rear lever arm and thereby prevents the knee joint from breaking. The recoil on the bolt head that occurs when the gun is fired is not absorbed by hinge pins, but by transfer surfaces that transfer the pressure to the front of the rear hinge. This carries locking elements there, more precisely curved locking surfaces that engage in counter bearings milled to fit on the barrel extension. When the moving part of the weapon moves backwards, the support joint breaks the knee joint, whereupon the rear joint swings out and the lock is released. The return, which is further controlled by the support joint, is reversed by the recoil spring, the weapon reloads and is ready to fire again.

Individual evidence

  1. Ulrich Eichstädt, "Snow cannons, eight biathlon rifles in the test", Visier, Das Internationale Waffenmagazin, Pietsch + Scholten Verlag GmbH, 02/1993 p. 40 ff
  2. Jaroslaw Lugs, Handfeuerwaffen, Military Publishing House of the GDR, ISBN 3-327-00032-8 , p. 306, p. 448, p. 454 to 455

literature

  • Automatic Weapons of the World , Copyright 1945 by Melvin m. Johnson & Charles T. Haven, publishers. William Morrow & Co, NY. UNITED STATES.
  • The Book of Rifles , Authors: WHB Smith & Joseph E. Smith, Copyright 1963 by The Stackpole Company, Harrisburg PA, USA.