The 38-40 Winchester (38-40 WCF) was introduced in 1874 in the Winchester Model 1873. It is based on the 44-40 necked down to a .401-inch diameter bullet, originally loaded with a 180-grain bullet in front of 40 grains blackpowder. Although never as popular as the 44-40, the 38-40 was chambered in a variety of lever-action and single-shot rifles. From 1878 the 38-40 was chambered by Colt in the Single Action Army and, later, Colt's Lightning slide action rifle and double-action revolvers. Current ballistics are about the same as the original blackpowder load, a 180-grain bullet at 1160 feet per second. Yielding just 538 foot-pounds, the 38-40 is extremely marginal for deer...but it was surely used by many settlers to fill the pot, as well as for personal defense. No new firearms have been chambered to 38-40 since 1937, but many rifles and revolvers so chambered are still in use.
