format_quoteSpringfield Armory standardized and introduced the 45-70 Government in 1873. The name indicated: 45-caliber, 70-grains of blackpowder, and a 405-grain bullet. An improvement over the 50-70-450, it had previously adapted to the Model of 1861 muzzle-loading rifle. The 45-caliber cartridge had significantly better ranging potential and was generally considered to be more accurate and, with less recoil, easier for most shooters to learn to shoot accurately.
A load introduced in 1879 and named the 45-70-500 (45-caliber, 70-grains of blackpowder, and a 500-grain bullet), was a major ballistic improvement, offering almost as much velocity and vastly superior long-range accuracy and delivered energy. This load still holds the record for shooting the farthest of any cartridge ever standardized by the U. S. Military for use in a battle-rifle! It can do this because the bullet remains stable to terminal range.
The other important Military load was the 45-56-405. According to the military records I read a long while back (if memory serves), this was introduced for one reason only, to reduce recoil in the Trapdoor Carbine. It launched the original 405-grain bullet at about 1100 fps, which about duplicated the full-house 500-grain load velocity when fired in the carbine so it gave similar trajectory across typical battlefield distances. While officially, the only reason this load existed was to ease discomfort for soldiers shooting the lighter carbines, I have no doubt the savings in propellant cost was also a consideration to the bean counters.
When loaded for safe use in early blackpowder guns using the best modern propellants the 45-70 is entirely suitable for big-game hunting of most species worldwide and can do so without generating sufficient recoil to cause most shooters grief. With the best modern loads at intermediate pressure and the appropriate bullet, it is entirely suitable for hunting any species worldwide. See the discussion under 45-70 (Lever-action guns)
As a target cartridge, the 45-70 has been extremely popular and effective since the 1880s. For example, in 1886, in competition at Creedmoor, a 1000-yard, 10-shot group of 8.6-inches, on-centers, was recorded and certified. This established a record that stood for more than 85 years. This was also the round used by the American team to win the famous Irish Challenge match at Creedmoor in 1873, which forever changed the world of target shooting and ushered in the cartridge-target-rifle era.
As with all cartridges used in guns with a tubular magazine, a properly applied crimp can smooth and ease chambering and a crimp is critical to lock the case mouth into the cannelure and thereby prevent recoil and chambering forces from driving the bullet into the case. In some instances, a roll crimp might be the best option But the Lee Factory Crimp Die usually does a better job and the crimp it applies will not damage a cast bullet as chamber pressure drives that from the case.
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