Thats Tom Knapp, never mind the gun Ill just take Tom along with his!
"A 45/70 has very similar recoil to a SG firing slugs."
Whats that got to do with high recoil pistols?
An 870 with slugs is a small weight to carry to save your life, if you can use it! Pepper spray is good too as backup.
But get real, most times the bear comes out of bushes close to you, there is no time to use anything, your best off lying still on the ground you may live through it.
If you get warning like has been said, make enough noise it knows your there, at the same time you can go for the slug gun, for if it doesnt work ( especially if its a female with cub/s) you would probably need to defend your self.
Not so long since a guy wounded a grizzly in Alaska, his professional guide went to finish it off leaving him with the truck, it ambushed him from behind a fallen tree and even though he emptied his 458 mag pistol into it it ripped him up terribly. Luckily another giude was out close to the area and heard the multi shots,knew ther had to be trouble and came and found him and got him airlifted to hospital, he just lived.
You cant do better than follow the advice given by the the Alaskan Fish and Game Service and it is free!
Better the man suspected of being a fool keep his mouth shut, than to open it and remove all doubt.