/*How loud are they because of the ports. i can take recoil but it is the noise that gets me to flinch. as I shoot a 7 rem mag and it provides a little discomfort as a noise factor*/
Please tell us that you aren't shooting these rifles without hearing protection! No use getting all geared up for buffalo and then getting stomped into jelly because you were too deaf to here one coming for you. Always wear hearing protection at the range or during practice...ALWAYS!!
As for the .45-70, I believe many reloading books show three power levels for that cartridge:
1. Trapdoor Springfield pressures
2. Lever gun pressures, as in the Marlin
3. Siamese Mauser & Ruger Number One
Anyone who would use a .375 Holland & Holland for the Cape Buffalo or the various Asiatic buffalo shouldn't have any reseervations using the Ruger Number One with the .45-70 loaded up to its potential in that rifle.
Factory loads, however, should give one pause to reflect, as they are loaded mild enough to be safe in the Trapdoors of 130 years ago...