Subcutaneous emphysema is often found in car accident victims because of the force of the crash. Chest trauma, a major cause of subcutaneous emphysema, can cause air to enter the skin of the chest wall from the neck or lung. When the pleural membranes are punctured, as occurs in penetrating trauma of the chest, air may travel from the lung to the muscles and subcutaneous tissue of the chest wall.
Both the Army and the Marine Corps teach that the maximum effective range of the M16A2/A3/A4 is 500 meters on a point target (individual enemy) and 800 meters on an area target (i.e. troops in the open).
The AK 47âs effective range is 100 to 800 mm. The feed system is a detachable box magazine (with 30 rounds). The adjustable sights are 378 mm (14.9 in). The size of the AK 47 gives it a muzzle energy of 2,010 joules (1,480 lbfâft). The cartridge measures 1.52 in (38.6 mm). The projectile weighs 120 gr or 8 grams.