Good meat damage...ehhh...you shoot a deer broadside...through the ribs, through the vitals, through the other side ribs. Unless you are considering the vitals like the heart and lungs and stuff like that as good meat...there's virtually no usable meat between the ribs bones or within the rib cage. And...there's a difference between ethical hunting and getting some kind of meat on the table lest the family starves to death. If you have to sacrifice a hind quarter to get the rest of the critter on the table...it becomes a moot point. Right?

Any gun you mentioned would kill any animal you mentioned within the rounds distance capabilities. People often overestimate the gun needed to kill the animal they are hunting. What determines which to use may be more a factor of hunting conditions. Where are you hunting in what terrain...wide open long distances or in the woods at short distances.

The 12 ga slug is a hard hitting pig. It's accuracy, in my opinion, is limited to 50-75 yards. Double that or a little more if you have a rifled slug barrel. In the deep woods where your shot might be limited to 50 yards or less, I can't think of much I wouldn't shoot with one. In an open field at 200 yards, I wouldn't take the shot.

I'm not familiar with the 45-70. Never seen one, never shot one, never knew anybody who owned one. Within it's range parameters, though, I would suspect it is more than capable of taking out a bore...for sure a deer.

I have known a few peeps with 243's. They use them for deer hunting out here. I would suspect it would take out a bore as well. I would think the bore with it's tough hide would be better taken with a solid tip bullet vs something you might use on a deer. That's something the more popular rounds usually give you...a greater variety of bullet weights and types.

I'm a big believer in the shotgun...you can hunt many types of critters depending on what you put in the chamber. Birds with bird shot, rabbits and squirrels, deer, bear, bore, and even people.

Between the .243 and the 45-70...if I had to pick, I don't think it would be much of a quandary, I'd go with the 243.

BUT...that's just me.

The best solution when it comes to deciding on which gun to get...get two or three of each. LOL