The gun has very few screws and springs. It is composed of about forty parts which may be taken down in the field. There are a few parts which can be assembled incorrectly and it cannot be determined that they are so assembled until the gun is ready to be put into action. At this point the gunner will find that the gun will not operate, therefore great care should and must be used in the study of a quick and positive assembling. The weight of this gun is about 30 pounds without water. This weight makes it necessary to use the gun on a tripod or other suitable mount. General Data. Weight of the gun—no water 30 lbs. Weight of the gun filled 36.75 lbs. Weight of the belt, 250 rounds 15.25 lbs. Length of the barrel 24 in. Weight of the belt, empty 7.5 oz. Sight graduated to 2800 meters. Rate of fire (shots per minute) 400-525. Aimed shots per minute 120. Calibre of bore .30 in. Weight of bullet 150 grs. Weight of cartridge 394 grs. Chamber pressure lbs. per sq. in. 47,000-50,000. Muzzle velocity (ft. per sec., theoretical) 2700. THE BROWNING AUTOMATIC RIFLE. General Description. The Browning Automatic Rifle, Model of 1918, is chambered for the United States standard ammunition. This rifle is classified as a light automatic rifle commonly referred to as the “Light Browning.” It has been fired 148 shots per minute, semi-automatic, while marching, and 110 shots per minute, semi-automatic, from the shoulder while in prone position. The rates of fire, which give the best results are from 80 to 100 rounds per minute, semi-automatic marching fire and 50 to 60 shots per minute, semi-automatic aimed fire. Operation.