Gunner500 answered ALL dumbassed questions as to whether the 45/70 "is enuff gun" for dang near anything
I gotta agree with you on this one, Jim!!
I expect you've got plenty of good answers on this thread already, stu, but just to gild the lily a bit, let me add my dos centavos.
I've shot about a dozen white-tailed deer and 1 pig with slow, heavy bullets, mostly with .50 or .45 cal muzzleloaders, but 3-4 with .45-70's. Out of that bunch, I've had two DRT's: a doe shot with a .50 cal 295 gr PowerBelt bullet, and a spike buck shot with a 350 gr .45-70 factory load. All the rest ran anywhere from 25 to 150 yards, then dropped dead.
I have no problem with the performance of any of those bullets, and I have no problem considering the 45-70 adequate for hunting any species in North America.
I have never been around a 45-70 very often and am not convinced of its stopping power on charging game.
Now, hold on thar, Bubba-Louey!!!
There is a HUGE difference between a
hunting rifle/caliber and a
stopping rifle/caliber. If you're talking about stopping a charging piece of Dangerous Game, you're talking about a specialized branch of the hunting sports. That specialized sport is practiced most commonly in the place where most of the planet's Dangerous Game species live, i.e., Africa. And even then, there are two levels of DG: thin-skinned (lion and leopard) and thick-skinned (elephant, rhino, and Cape buffalo).
What the African PH's will tell you almost to a man that you can hunt anything up to and including elephant with a rifle of the 375 H&H class, but that a
stopping rifle for thick-skinned DG should be a big bore (.40 caliber at least, and preferably larger) firing a 400+ grain solid bullet at 2200-2300 fps. There are all kinds of theories for why this is the "magic" combination, but the fact is that no one really knows why that is the case. But it works, and it's been working for 100+ years, so no one argues with it any more.
As long as you put the bullet where it will kill the incoming animal, that is. This means the brain or high spinal cord, of course. You can shoot a charging elephant with a 450 gr bullet in a suitable caliber and still be killed by it, as PH Kevin Gibson demonstrated earlier this year.
So shot placement still counts, regardless of caliber.
For thin-skinned DG, however, many PH's go much lighter, using anything from the 375 H&H with a 300 gr soft bullet to a 12-gauge shotgun stoked with 00 buckshot, depending on the situation.
Since thick-skinned DG is a rarity in North America, we're really talking about the latter category: bears. And a modern 45-70 loaded with hot ammo (appropriate to the action and steel used in manufacture) fits the bill, ballistically speaking.
A modern Browning or Winchester 1886 is easily capable of withstanding 50,000 PSI pressures. This means you can load 'em up considerably. Extreme example: I've worked up loads for ~400 gr cast bullets at velocities above 2100 fps. That's close to 4000 fpe, and awfully close to the level of an African express
stopping rifle. This load recoils immoderately in a light rifle, you need a fullsize rifle to tame the kick... but if that isn't a North American stopping rifle and load, I don't know what is.
Personally, I don't think there's much I wouldn't be afraid to take on in North America with a good lever action 45-70 with a good 300 gr soft point bullet at 1900-2000 fps.