The high performance 45-70 is possibly the most reliable 200-yard heavy game caliber available. Although it must be considered an ancient caliber, the reasons for its capabilities are generally not well understood. This is primarily the result of a general misunderstanding of how best to load the caliber for maximum effectiveness against heavy and dangerous game. The rules that apply to the building of ammo for other calibers are commonly applied to the 45-70 and, consequently, tend to limit the caliber's effectiveness.
It is extremely common for shooters to prefer relatively small calibers that produce high velocity and flat, long-range trajectory. This is evidenced by the overwhelming popularity of calibers such as the 30-06 Springfield, 7mm Magnum, and 300 Winchester Magnum. These calibers work with fairly small diameter bullets that require expansion in order to produce reasonably quick kills. Simply stated, the price paid for flat trajectory with modest recoil is bullet diameter insufficient to produce quick kills with non-expanding bullets.
By contrast, the 45-70 is not a long-range cartridge, but within its 200-yard range it offers some extremely significant advantages over all smaller diameter calibers. Primary among these is the 45-70's ability to utilize extremely blunt non-expanding hard-cast bullets. This is the case for a couple of reasons. First, unlike the great majority of bolt-action rifles, the 45-70 lever-action rifle is configured so as to allow the reliable transit of blunt nose cartridges from the magazine to the chamber. By their nature, most bolt-action rifles will not reliably feed blunt bullets from the magazine to the chamber, and, consequently, require roundnose bullets, usually solids, whenever great penetration is required. This is a grave shortcoming, as roundnose solids are notorious for their lack of quick incapacitation. Second, owing to the substantial diameter of the 45-70, blunt non-expanding bullets produce wound channels entirely adequate to produce quick kills on big game. No expansion is required. This subject of adequate wound channel diameter is also influenced by the diameter of the frontal flat on the bullet (meplat). In fact, meplat diameter is more significant than bullet diameter with regards to the actual diameter of the penetration channel produced. In other words, the blunter the bullet the wider the wound channel. Due to the large diameter of the caliber and the lever-action rifle's ability to reliably chamber very blunt nose cartridges, the 45-70 is capable of delivering nearly unparalleled impact effect against heavy game, with super deep bone-crushing penetration and quick incapacitation effect.
Owing to this ability, the 45-70 provides a degree of lethality not generally found with other calibers, even ones producing much greater power. This is best evidenced by comparisons with the mighty 458 Winchester Magnum. As conventionally loaded with 500-grain expanding bullets, the 458 is notorious for its relatively shallow penetration. Consequently, when really heavy game is hunted, it is quite common for roundnose solids to be used. Unfortunately, roundnose solids tend to be slow to incapacitate big game. By comparison, the 45-70 can be loaded with blunt non-expanding hard-cast bullets that produce much deeper penetration than the 458 with expanding bullets, and cut a much larger wound channel than the 458 with roundnose solids. Also, the speed of incapacitation is much faster with a blunt non-expanding bullet than with any roundnose solid. Simply stated, proper hard-cast bullets effectively split the difference between under-penetrative expanding bullets and the slow to incapacitate roundnose solids.
The only significant limitation of the 45-70 is the 200-yard trajectory. However, within that range, the 45-70 can anchor the heaviest game on the planet with brutal authority. It can shoot lengthwise through the heaviest game animal including buffalo with large caliber blunt bullets, giving the shooter the advantage of not having to pass on bad-angle shots. If the bull of a lifetime is headed straight away from the shooter and the seat of the pants shot is all that is offered, the shooter can take the shot and know that he will reach the vitals. Generally, when proper hard-cast bullets are used, lengthwise shots result in exit wounds. If confronted by a heavy coastal grizzly hell-bent on annihilation, the 45-70 lever-gun will reliably shoot lengthwise through the bear, while providing the quickest action type available, the lever-action, should a rapid follow-up shot be required. This exceptional combination of action speed and impact effect is impossible to beat when the skirmish is close, and the game is dangerous. And as it turns out, the caliber is also capable of outstanding accuracy, on the order of MOA. If I could own only one big game rifle, it would certainly be a 45-70 lever-gun.
- Randy Garret
http://www.garrettcartridges.com
Randy Garrett http://www.garrettcartridges.com
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