The wheel lock mechanism has been more efficient to lock open than the old matchlock. Trigger break, primer, and primer ignition were almost simultaneous. For the first time in history a pistol could be loaded and then cocked upon demand for use. A magazine could be rapidly expanded into a fully loaded weapon.
Wheel Lock Mechanism
During World War I, the United States military adopted the wheel-lock mechanism for all their automatics. Many of these devices were put into production by the manufacturers in mass quantities. These devices allowed the operator to cock the pistol without striking the trigger as with the older matchlocks. After the war the American military retrofitted many of their automatics with trigger releases instead of the old matchlock and primer ignition systems.
Early 20th century firearms designers paid close attention to the improvement of the wheel-lock mechanism flat bed trailer. Many modifications were made that permitted the use of pistol ammunition in semi automatic and fully automatic firearms. After World War II, Germany, Japan, and Italy all adopted new types of ammunition that utilized pyrite to increase firing rates. Pyrite is a very soft powder and it provided increased muzzle energy, which lead to an increase in effectiveness in many military weapons.
Patent laws allowed the patentability of many mechanical inventions. The wheel lock systems was one of these inventions. The American patent office approved this design by allowing patents to be filed by individuals other than the inventors. This helped the mass production of wheel lock systems.
A German engineer namedfriedrich nrberg was credited with the design of the pin-lock mechanism. A patent was granted in 1931 to him by the Weingard patent office based in Nuremberg, Germany. This was the first patent awarded by this office. His design was based on the British mechanism described in 1827. A steel wheel was used as the handle and the pins were placed in a slot in the top cover.
An Improved Metal Wheel Lock Pistol was designed by R.W. Mulchmore for the US Army’s Chemical Service Company. He believed that a pistol could be designed for the soldier that carried it because “he did not wish to take the danger of discharging the weapon when his attention was diverted by some bodily hindrance.”
The Improved Metal Wheel Lock Pistol or PMP was designed to overcome this problem. Its primer would be the same color as the belt buckle or other fastening device used to secure the pistol. As the soldier put his weapon away the primer would pop out and be used to strike a primer catch located in the base of the charging handle and thereby set off the firing pin. This was much simpler than the opening of an earlier model of the pin-locking arm which required a spring that had to be loaded manually after pulling the trigger or after manually cranking the bolt.
The Improved Metal Wheel Lock Pistols was later adopted by the British military and was used in their muskets and handheld carbines. American troops later adopted the same type of pistol and soon it was adopted by the Mexican army as well.
One of the most commonly known variations of this lock mechanism is the double cocking safety. In this design two screws are fixed in a clip that extends from the base of the pistol to a slot in the buttstock and both screws simultaneously cock the firearm, thus ensuring the firearm is ready to fire upon the insertion of a magazine.