The M1841 Iron 6-pounder field gun fired a 6.1 lb (2.8 kg) round shot up to a distance of 1,523 yd (1,393 m) at 5° elevation. It could also fire canister shot and spherical case shot. The cannon proved very effective when employed by light artillery units during the Mexican–American War. The cannon was used during the early years of the American Civil War, but it was soon outclassed by newer field guns such as the 12-pounder Napoleon. In the US Army, the 6-pounders were replaced as soon as more modern weapons became available and none were manufactured after 1862. However, the Confederate States Army continued to use the cannon for a longer period because the lesser industrial capacity of the South could not produce newer guns as fast as the North.