Well, now, the .45-70 is a new one for high speed, although I recall one writer in an old Gun Digest from about 50 years ago commenting on how there's weren't as many loads around for the .45-70 like there used to be. But judging from the listings in old publications like the Gun Digest, there was hardly any variety to begin with among the different calibers. That may not be such a bad thing at that. The .38 Special did come in two or three different loads, including a "metal piercing" round, as mentioned already, but there didn't seem to be much of a selection of bullets like there is now.
Shoot low, sheriff. They're riding Shetlands!
Underneath the starry flag, civilize 'em with a Krag,
and return us to our own beloved homes!
Buy War Bonds.