I"ve loaded some hot 45-70 Gov for my Marlin Guide Gun that makes me cringe when I get my finger anywhere near the trigger. Those Hot 405 grain load will kills on both ends. Loads lately have been for Rolling Block rifle and I keep them pretty mild,
I can relate to that, my first 45-70 was a Browning BPCR Loaded some moderately heavy loads and could only take 10 from a bench. It had been a bunch of years since I had shot anything that recoiled heavy, ie my Win mod 70 Featherweight 30-06.
One of the worst I now have is a Marlin 1895 cowboy and it is rough with heavy loads. Ruger #1's in 375 H&H and 458 Win mag are not any fun off a bench with full loads.
My Guide Gun is a handful, the standard 1895 is pleasant by comparison, a Win 1886 repro in 45-70 with crescent butt plate can hurt shootiing from a bench in spite of the heavy weight.
My conclusion is that the heavy thumpers are meant to be shot from a standing position or if sitting at least from a very upright position. One range I go to requires that centerfire rigles be shot through a slot in a fence intended to prevent shooting over the berm so I no longer go there with these rifles. It's strange that they will allow hihg power handguns to be shot offhand there.