45-70 Ammo History and Specifications
The .45-70 rifle cartridge, also referred to as the .45-70 government, has a rich history and despite having been around for more than a century, it still remains popular as a specialty cartridge. The .45-70 evolved as a military cartridge but today remains a very popular hunting round. The 45 refers to the nominal diameter of the bullet (inches) and the 70 refers to the weight of the gunpowder (grains). At short distances, the ammunition has a muzzle velocity ranging between 1,200-1,400 fps.
The .45-70 ammo was first developed in the late 1800s by the US Army. It was a replacement for the .50-70 government cartridge that had been manufactured in previous years. The predecessor to the .45-70 was the .50-70-450 cartridges which were widely used from 1866 to 1873. It was popular among hunters but then the military decided it wanted something more accurate, with more range and penetrating power. The initial .45-70 had 55 grains and was ideal for the Springfield trapdoor rifle.
Over the next few years, a newer variation of the .45-70-500 was made. This heavy bullet was significantly superior and could easily reach ranges of 3,350 yards; it also proved to be lethal at those distances.Within the next several years the .45 caliber Springfield underwent several modifications and at the same time as the new 500-grain bullet was manufactured for use in stronger firearms. At that time the M1873 and M1884 Springfield rifles were the key small arms of the US military. Both the US army and Navy used the .45-70 ammo in a number of guns and rifles. The .45-70 last saw its highest use by the military during the Spanish-American war and then was only used sporadically until the beginning of the 20th century.
The .45-70 cartridge is still in use today by the US military in a number of models of line-throwing guns. The early models of these line launcher guns were made from modified sharpshooter and trapdoor rifles, while the later models were built on break-open single shot rifle actions. These line launchers use the 45/70 caliber and are capable of throwing a rope from 350’ up to 700’ depending on the rope weight, cartridge load and wind conditions.
The .45-70 has a rainbow trajectory with the bullet significantly dropping yardage at ranges more than a few hundred yards. The ammunition has a minimum acceptable accuracy of 4 inches at 100 yards but is not much more effective at yardage of more than 300 yards.