
Dave

Well, to be perfectly honest, I have never used Triple Seven with a filler either. I fact I have no liking for T-7 at all. For the 45-70, I have a Plainsman shooting partner who loads with a 454 round Ball. Ball weight was 150Gr. Very pleasant load to shoot.
My personal loading for Plainsman has been my 38-55, full case APP and 90Gr .380 EPP UG - 36 Bullet. Very pleasant indeed.
You will find, felt recoil, and recoil in general is more a product of the weight of the Projectile than the actual powder charge.
Understanding, none of this missive actually. addresses your original question, nor provides any help in your quest. However, it's Saturday Morning. It's some dam'd cold out there, I'm not shooting, I'm a mite bored so here I am. You may wish to ignore this missive, as I know I would, but if you're reading this part, it's too late anyway. Coffee is hot however. Enjoy.
People be Hazardous to Yer Health - Beware!!