Push vs whack? In a heavy revolver, like a Ruger Blackhawk/Vaquero or large frame S&W, recoil of standard velocity 44-40 nitro loads is "mild", call it a push if you want. BP loads fully equal to original 44-40 BP loads get beyond "mild", right up there with modern 45 ACP loads, maybe even with what I remember with early 45 ACP loads.

Load that 44-40 revolver with true HV loads (as loaded by factory in early 1900s for rifles), which were NOT recommend for revolvers (meaning Colt SAAs, S&W, etc., typical of late 1800s, early 1900s) and it has a really sharp whack and muzzle blast, just like a 44 Mag with similar 200 grain loads in a Ruger Blackhawk/Vaquero.

Oddball calibers?? I have been using 44-40 for so long it is more of a standard caliber, like 32-20, 7X57, 16 gauge, etc.

Niklas