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Breech Mechanism for Semi-Automatic-Gune
This design of Breech Mechanism is embodied in the 3 "U.S. Naval Guns, 3" Anti Aircraft uns of both the U.S. Army and Navy, and 75 mm Army Guns; and its remarkable efficiency and great superiority over other systems have been thoroughly demonstrated in actual service.
The Breech Block is of the sliding wedge type. The pressure is taken by a series of ribs which distribute the pressure over an extended surface.
The power for operating the mechanism is derived from the Recoil. The functioning of the mechanism, however, occura on the Counter Recoil, the Breech remaining closed and locked all during the Recoil and only starting to open at the latter part of the Counter Recoil. This insures the absence of pressure, when the Breech is opened.
After the Breech has been opened for the insertion of the first cartridge, the orly manual labour required for continued firing is loading and pulling the trigger, the operation of the mechanism berg performed automatically by the Counter Recoil.
Fol
very rapid firing, even the time for pulling the trigger is eliminated by holding the trigger back, as long as the gun is on the target.
The design of Breech Mechanism is suitable for all types of Field-Mountain, Anti-Aircraft and Naval Guns, from 37 mm up to and including the 5 inch.
The following U.G. Army and Navy Guns employ this
Mechanism
106 U.. army Anti-Aircraft (60 Cal.) gun
3 inch U.S. army Anti-Aircraft Gun (50 Cal)
75 mm U.8. army Field Oun
3.inch U.9.Navy Anti-Aircraft Gun (50 (al)
3 inch U.S.Navy Broadside Gun (50 Cal.)
3 inch U.S.Navy Submarine Chaser Gun (23 cal.)
For Anti-Aircraft purpoees, the Mechanism cannot be excelled. The great Rapidity of Fire, unequalled by any other high-powered gun of this size and which is necessary for Anti- Aircraft purposes, can be as readily maintained at high angles of elevation as at the horizontal position.