From Wikipedia, the free encyclopedia:
"The .45-70 rifle cartridge, also known as .45-70 Government, was developed at the U.S. Army's Springfield Armory for use in the Springfield Model 1873 .45 caliber rifle, known to collectors (but never to the Army) as the "Trapdoor Springfield." The new cartridge was a replacement for the stop-gap .50-70 Government cartridge which had been adopted in 1866, one year after the end of the American Civil War.
The predecessor to the .45-70 was the short lived .50-70-425 cartridge, adopted in 1866 and used in a variety of rifles, many of them percussion rifled muskets converted to trapdoor action breechloaders. The conversion consisted of milling out the rear of the barrel for the tilting breechblock, and placing a .50 caliber "liner" barrel inside the .58 caliber barrel. The .50-70 was popular among hunters, as the bigger .50 caliber bullet hit harder (see terminal ballistics) but the military decided even as early as 1866 that a .45 caliber bullet would provide increased range, penetration and accuracy. The .50-70 was nevertheless adopted as a temporary solution until a significantly improved rifle and cartridge could be developed.
For comparison: a .30-06, .45-70, and .50-90, respectively. The result of the quest for a more accurate, flatter shooting .45 caliber cartridge and firearm was the Springfield Trapdoor rifle. Like the .50-70 before, it, the .45-70 used a brass center-fire case design. A reduced power loading was also adopted for use in the Trapdoor carbine. This had a 55 grain (3.6 g) powder charge.
Also issued was the .45-70 "Forager" round, which contained a thin wooden bullet filled with birdshot, intended for use hunting small game to supplement the soldiers' rations. This round in effect made the .45-70 rifle into a 49 gauge shotgun.
The 45 caliber rifle underwent a number of modifications over the years, the principal one being a strengthened breech starting in 1884. A new, 500 grain (32 g) bullet was adopted in that year for use in the stronger arm. The 45 caliber rifle was the principal arm of the US Army until 1893, long after European adoption of efficient repeaters using smokeless powder ammunition had made the American weapon obsolete as a military rifle. It was last used in quantity during the Spanish-American War, and was not completely purged from the inventory until well into the 20th century. Many surplus rifles were given to reservation Indians as subsistence hunting rifles and now carry Indian markings.
The .45-70 cartridge is still used by the U.S. military today, in the form of the CARTRIDGE, CALIBER .45, LINE THROWING, M32, a blank cartridge which is used in a number of models of line throwing guns used by the Navy and Coast Guard. Early models of these line throwing guns were made from modified Trapdoor and Sharps rifles, while later models are built on break-open single-shot rifle actions
As is usual with military ammunitions, the .45-70 was an immediate hit among sportsmen as well, and the .45-70 has survived for one and a third centuries. Today, the traditional 405 grain (26.2 g) load is considered adequate for any North American big game within its range limitations, including the great bears, and it does not destroy edible meat on smaller animals such as deer due to the bullet's low velocity. It is very good for big game hunting in brush or heavy timber where the range is usually short."
.45-70. (2009, March 1). In Wikipedia, The Free Encyclopedia. Retrieved 13:55, March 23, 2009, from http://en.wikipedia.org/w/index.php?title=.45-70&oldid=274272828