Muzzle booster

A muzzle booster or recoil booster is a device fixed to the muzzle of a firearm, intended to harness the energy of the escaping propellant to augment the force of recoil on portions of the firearm. In spite of its name, a muzzle booster does not increase muzzle force or velocity but instead is usually used to improve the reliability and/or rate of fire of a recoil operated firearm. It was invented by Hiram Maxim in 1894. The muzzle booster is distinct from the muzzle brake, which is designed to use the propellant gases to reduce the recoil of the firearm. However, unlike a muzzle brake, a muzzle booster uses the pressure of the expanding gases, rather than the reaction force, and it does not alter the felt recoil of the weapon, it merely adds more energy to the operating components. When Hiram Maxim had his machine gun trialed by the US Navy in their new 6 mm smallbore cartridge in the summer of 1894, he noticed that the lack of recoil from the latter was negatively impacting his design. In his patent application on an "apparatus for increasing the recoil energy" in October of the same year the inventor stated: "It has been found that with cartridges such as those above referred to the recoil energy is in some instances too feeble to satisfactorily operate the breech mechanism". Recoil boosters (avant la lettre) similar to his patent were imported to Russia and after some modifications were adopted in the M1905 3-line machine gun, while another derivative was adopted by Germans in 1915 on their MG 08 guns. A later type of a recoil booster designed in 1904 by Trevor Dawson and J. Ramsay of Vickers, Sons & Maxim in 1904 was adopted by the US Army on their Maxim Machine Gun, Caliber .30, Model of 1904, as well as the British on the Vickers machine gun of 1912. At firing, the recoil from the cartridge pushes the barrel and bolt together backwards within the gun. This movement provides the energy required to extract and eject the spent cartridge, and compresses the recoil spring to complete the cycle.