A 45-70 shoots like a rainbow, the further away a target is the higher you need to aim. For any of the animals that you listed except for the brown bear I would have to say that 150 yards would be max. For the bear I would keep it under 100 yards just for the simple fact that you don't want to make him mad.
A lot of brown and black bears have fallen to that round and I would figure that most of them have been under 100 yards.
I totally agree with you critter on the 150 yds with the 45-70. Like you mentioned they have a trajectory like a rainbow. Definetly would'nt be my 1st choice for an open area where shots could surpass 200 yds
Has enough omph to do the grizzly but I'd limit the rangs to 100yds or less. not that it won't do it farther but you shoot better at 100yds than ay 150! If you are innharms way, and if you wound a grizzly, that is where you may well be, you need to make the best most accurate shot you can!
I must admit that I have missed a big game animal with a rifle. And not only was it a bull elk, it was the largest bull that I have had in my sights with a tag in my hand. But, as with most "missed shot" stories, I have an excuse. Moisture doesn't really ever bode well for hunting equipment. When moisture (either rain or snow) gets into a firearms barrel, nothing good takes place. A couple rain drops down there can change the point of impact drastically and a barrel jammed with snow after a...