First off, use the gun and caliber you really like. For me, a major part of the enjoyment of the hunt is the gun and caliber I am hunting with. I usually use old Winchesters that are a hundred years old or more. Second, if you do want to use a .45-70, you will have no problem at all shooting out to 200 yards, provided you know what the range is. That means you have a range finder for those longer shots. You must also have idea of the trajectory of your bullet. With a rangefinder and knowing the ballistics, you are good to 300 yards, if you sight in for 150 yards. I do not have a rangefinder, but I practice out to 200 yards with my .45-70. My general rule of thumb for my ballistics is that if it looks to be between 150 to 200 yards away, then I aim for the spine and I know that bullet is going through the 'boiler room'. If it looks to be 80 to 150 yards away, then I aim for just behind the shoulder and half way between top and bottom and I know that bullet is going through the 'boiler room'. If it is less than 80 yards away, then I aim low behind the shoulder and I know that bullet is going through the 'boiler room'. I shoot iron sights, but if you have a stainless steel Marlin 1895 with a scope, you are laughin'. (provided you practice). I see some jaw-dropping ineptitude at the range by those who do not practice. Do not leave it until the day before the hunt.