A good way to learn about a cartridge and what it will do is to decide on a bullet weight and shoot it. A lot.
In the 45-70, there is a lot to choose from, 300, 330, 350, etc, etc.
Pick one and learn it.
In the 405 WCF, Winchester wisely choose on standard bullet weight, 300 grain. And they ran it at about 2200 fps.
Not too shabby. When it was introduced, before all those who never shot it said the buttplate would cut your arm off, it was considered to be too BIG for North American game.
I have the Lyman bullet mold, 412263 and am considering having it hollowpointed for some variety and because I like the Gould bullet in the 45-70.
The one thing the 405 lacked was a variety of rifles chambered for it. Winchester made the 1895 lever gun and a couple of bolt rifles on the M70 action, Ruger makes the single shot. In England there were a half dozen double and single barreled rifles built. With the exception of some custom bolt guns, that is it.
The 45-70 is available in everything except a semi auto, unless you count the Gatling.