The 14-pounder James rifle or James rifled 6-pounder or 3.8-inch James rifle was a bronze muzzle-loading rifled cannon that was employed by the United States Army and the Confederate States Army during the American Civil War. It fired a 14 lb (6.4 kg) solid shot up to a distance of 1,530 yd (1,400 m) at 5° elevation. It could also fire canister shot and common shell. Shortly before the war broke out, the U.S. Army adopted a plan to convert M1841 6-pounder field guns from smoothbore to rifled artillery. Rifling the existing 6-pounders would both improve the gun's accuracy and increase the weight of the shell. There were two major types produced, both were bronze with a bore (caliber) of 3.8 in (97 mm) that would accommodate ammunition designed by Charles Tillinghast James. The first type looked exactly like an M1841 6-pounder field gun. The second type had a longer tube with a smooth exterior profile similar to a 3-inch Ordnance rifle. At first the rifles were quite accurate. However, it was discovered that the bronze rifling quickly wore out and accuracy declined. None of the rifles were manufactured after 1862, and many were withdrawn from service, though some artillery units employed the guns until the end of the war.

The M1857 12-pounder Napoleon or Light 12-pounder gun or 12-pounder gun-howitzer was a bronze smoothbore muzzle-loading artillery piece that was adopted by the United States Army in 1857 and extensively employed in the American Civil War. The gun was the American-manufactured version of the French canon obusier de 12 which combined the functions of both field gun and howitzer. The weapon proved to be simple to produce, reliable, and robust. It fired a 12.03 lb (5.5 kg) round shot a distance of 1,619 to 1,680 yd at 5° elevation. It could also fire canister shot, common shell, and spherical case shot. The 12-pounder Napoleon outclassed and soon replaced the M1841 6-pounder field gun and the M1841 12-pounder howitzer in the U.S. Army, while replacement of these older weapons was slower in the Confederate States Army. A total of 1,157 were produced for the U.S. Army, all but a few in the period 1861–1863. The Confederate States of America utilized captured U.S. 12-pounder Napoleons and also manufactured about 500 during the war. The weapon was named after Napoleon III of France, who helped develop the weapon.