And to be honest, the .45-70 SEEMS like it would offer a huge hydrostatic shock, but in practice, it really doesn't. It hits pretty hard initially because of it's big diameter, but the temporary cavity (a measure of hydrostatic shock and stopping power) is actually much smaller than that of say a .30-06, even though it has about 40-50% more energy. The .45-70 is moving SLOW, so tissue (the "hydro" part) has more time to move out of the way, rather than accepting damage (the "static" part).

Personally, the only reason I want an exit wound is for blood trail. Arguing that a bullet transfered MORE energy if it exits is simply wrong. Keith's comments were that a bullet that FRAGMENTS, wastes energy. A bullet that fragments is wasting energy. For example, getting hit in the face with 1lb of sand sucks, but doesn't really hurt, getting hit in the face with a 1lb rock pretty much ruins your day. However, simple physics proves that a bullet that exits did NOT transfer more energy than a bullet that stops in the animal. The only difference is how efficiently that energy was transfered, and how much damage resulted FROM the transfer.


What I want from a deer hunting bullet is about 2x diameter expansion, and 80%+ weight retention. In general, that should give me a golfball to tennisball sized exit wound on a heart and lung broadside hit. In general, that range of damage gives me quick drops, but would offer relatively controlled meat loss if I happen to hit the a shoulder. It also means my bullet is HARD/TOUGH enough that if I DO hit the shoulder, it will probably break it, rather than deflecting and "giving up". I have used rounds that gave more AND less exit wound, and frankly, they either did too much meat damage, or didn't drop enough blood trail.

A deer running 50yrds and dying is a good day. There is no reason that getting sudden heart and lung trauma should drop any animal in its tracks. Sudden imobilization is caused by hydrostatic shock, which effects the CNS. If you're using a bullet that's too hard, that drills a hole straight through your target, it won't generate much hydrostatic shock. If you use a bullet that fragments, you won't generate much hydrostatic shock. If you use a bullet that mushrooms to 2x of it's original diameter, but doesn't break apart, it's very likely to exit (penetration is improved due to the good weight retention), and it's very likely to do a LOT of damage along the way, producing a huge temporary cavity and a huge hydrostatic shock wave. Temporary cavity is a big deal for me, that suggests how extreme the hydrostatic shockwave really is. The easy test is shooting gallon jugs of water. The bigger the water spray, the better the hydrostatic shock.

If you reload the .45-70, contact your bullet manufacturer to find the proper velocity range for expasion. Some .45-70 bullets are designed more like handgun bullets, so they'll expand south of 1000fps. The problem is that if you push them up over 2000fps and hit a deer at 20yrds, the bullet is very likely to fragment (bullet failure), and not give very good wound characteristics. But the same bullet at 100yrds might perform flawlessly.