45-70 recoil varies greatly. If you shoot your standard remington 405gr 20KPSI loads, its like 180gr out of a 308win. If you shoot higher pressure corbon loads, it can get sporting very quick.
I have loads with 300gr up to 2200fps that kicks like a mule. I have some 500gr lead loads at 1850fps that kicks like a 300win mag.