A quick check on Loaddata.com revealed the standard pressure for a 45-70 load is 28,000 PSI.
There are loads listed for 58,000 PSI that push a 500 grain bullet to 1,870 fps.
I also found one load listed for a 400 grain bullet at a little over 2,000 fps.
That is not 458 Winchester velocity and power but it is darn powerful.
I load 500 grain bullets for 2,140 fps in my Heym double and could go a little faster if for a bolt action rifle.
The Speer reloading manual lists the 45-70 under three different load uses: historic (think the old trapdoor springfields) modern lever actions, and modern single shots (Ruger, Browning) which have the strongest of the three action types.
I have shot the Buffalo Bore 45/70's in a Marlin lever. To this day, it's the ONLY gun/load that has about knocked me senseless from the scope coming back to bite me, HARD! You better have a really good grip on the forestock!
I have great love for my 45-70s and have loaded them up the max for my rifles and down to powder puffs and I tell ya it's a cool round , there's a bunch of stigmas or scrutiny over power levels etc but its come a long way from when it was an old government round and so has the 458win , the 458wm had a little bad rep too for a while
That being said I dont think the 45-70 is gonna be in the same class as the 458wm but I do love a 45-70 so much I have a double coming in one !
Now you are ready to move up to an 1886 45-90!
My 1886 45-90 took ele, several cape buff, leopard, etc in Africa . Plenty game in the US too.
Top load for ele was North Fork 450 grain flat point solid at 2150 fps (all at safe pressures).
It is the bullet that kills and not the rifle.
I am now breaking in a Beretta DR in 45-90. Good sport. Doing velocity tests this weekend.
The modern 45-70, loaded to the gills in a strong rifle can almost kind of sort of match what the original defective 458 Winchester rounds did. The rounds that gave it a reputation for being dangerously underpowered, and is still talked about 50 years or more after they fixed it. Somehow, that makes the 45-70 appropriate for Buffalo hunting in some circles. Doesn't add up for me.
I know it killed millions of bison, but they aren't the same beast. And I know it will kill a Cape buffalo. So will my 30-06, or my son's 243 for that matter. Doesn't make any of them appropriate rounds for cape buffalo. Appropriate isn't about killing it on a perfect broadside presentation. It's about stopping it from a suboptimal angle when the chips are down.
The buffalo in the second video dropped quickly because the second shot disrupted the nervous system in some way. I couldn't tell what the hit was exactly, but animals don't drop like that from blood loss. When they bleed out, they slow down and stagger and fall. Maybe he put it in the animal's ear or hit the high shoulder or spine, I couldn't tell. It wasn't the amazing power of the 45-70, that much I know.
it's a great round and it is capable of things the original designers couldn't dream of. And yes, it will kill a buffalo and no doubt an elephant with the right bullet and bullet placement. But it is close to a stunt, which is entirely fine by me if done by someone who understands exactly what they are working with and has enough knowledge and respect for the animal to do it cleanly. To me, it is no different from using a handgun or a bow- if you have the expertise and the patience, it can be done, and the extra challenge has appeal But these are things for the experienced hunter. A 45-70 just isn't an appropriate tool for the vast majority of buffalo hunters, no matter how good a job it does on the two animals that died cleanly enough to be used in the promotional video.
Some seem to have skipped the part where I reminded all that it is the bullet that does the killing, not the rifle. It has long been understood that the proper bullet at 2150 fps will kill Cape Buff and ele and such and this has repeatedly proven to be true.
The source of the bullet is irrelevant if the bullet is aimed properly, so why argue about whether it comes from a muzzle loader, a DR, a bolt action, lever action, or single shot Ruger #1 ?
Unless of course your objective is just to win an argument, which is rather childish. Unless your opinion is solicited, keep it to yourself and bask in the knowledge that you know what is best for all others.