named. The British Army began naming their American tanks, although the U.S. Army never used those terms until after the war. The M3 tanks with the British turret and radio setup received the name "General Grant", while the original M3s were called "General Lee", or more usually just "Grant" and "Lee". The M3 brought much-needed firepower to British forces in the North African desert campaign. The 75 mm was operated by a gunner and a loader. The 75 mm gun used an M1 periscope, with an integral telescope, which was mounted on top of the sponson for sighting. The periscope rotated with the gun. The sight was marked from zero to with vertical markings to aid deflection shooting at a moving target. The gunner laid the gun on target through geared handwheels for traverse and elevation. The 37 mm was aimed through the M2 periscope, though this was mounted in the mantlet to the side of the gun. It also sighted the coaxial machine gun. Two range scales were provided: 0- for the 37 mm and 0- for the machine gun. Of the 6,258 M3s produced by the U.S., 2,855 were supplied to the British Army, and about 1,368 to the Soviet Union. Consequently, one of the American M3 medium tank's first actions during the war was in 1942, during the North African Campaign. British Lees and Grants were in action against Rommel's forces at the disastrous Battle of Gazala on 27 May that year. They continued to serve in North Africa until the end of the campaign. A regiment of M3 Mediums was also used by the U.S. 1st Armored Division in North Africa. In the North African campaign, the M3 was generally appreciated for its mechanical reliability, good armor and heavy firepower. In all three areas, it outclassed the available British tanks and was able to fight German tanks and towed anti-tank guns. The tall silhouette and low, hull-mounted 75 mm were severe tactical drawbacks, since they prevented the tank from fighting from hull-down firing positions. The use of riveted armor led to a problem called "spalling", whereby the impact of enemy shells would cause the rivets to break off and become projectiles inside the tank. Later models were welded to eliminate this problem. The M3 was replaced by the M4 Sherman as soon as these were available, though several M3s saw limited action in the battle for