Sorry - I am not ready to "stay home and watch hunting programs on TV"! I enjoy experiencing the outdoors but there are some hazards associated with it. I think it's responsible to try to prepare for these hazards. I will continue to carry bear spray and if possible this will be my first line of defense but I prefer to have a plan B. I owe it to my kids need to do what I can do to home at the end of the day.
OK, I was a bit flippant pent on my first response, but considering that the question was asked in good faith let me reply likewise.
There is no perfect stopping rifle. Big is better to a point, but that point is reached when the rifle gets too big and heavy, kicks too much or is not suitable for the game being hunted. Double rifles may be ideal in Africa for the PH backing up clients shooting elephants, rhinos, hippos and cape buffalo, but does a US client really need this powerful gun? Traditionally stopping rifles in Africa have been heavy double rifles, but double rifles have not been as popular in the US. Just as well, they are expensive, not that accurate and so specialized you are not going to be able to use them for multiple uses. As for the cost of ammo, that is as painful as the recoil! Since, you have indicated, your stopping rifle is plan B, I think you can dismiss the African heavy thumpers.
So what are we talking about? We are talking about something that can be use effective against the big bears of the western states, Canada and Alaska. Moose, possibly Buffalo, and mountain lion. I have not included black bear here since their response to humans is more akin to a pray species than an aggressive predator. (If you want to do some follow up research you might want to contact the Bear Research Center, Ely MN)
What I did like about your thread was your willingness to use pepper spray as a fist line of defense. Pepper spray has proven to be effective, when use correctly, in encounters with aggressive bears. I suggest that you purchase two Counter Assault Bear Deterrent containers, one to carry, and the smaller, 8.1 ounces, to train with. I am seeing more guides carrying this product which gives me faith in the product and its effectiveness. You can also see videos on the internet of the spray being used. You will not be waisting your money by actually doing a test spraying. If you are really faced with a life and death situation, it is no time to be fiddling with the safety tab, or wondering which direction the spray comes out. Follow the label watch the videos.
I have seen hunters in Montana with 375 H&H rifles and I have taken mine out just for the fun of hunting with it. The problem is, they are dam heavy and when you are hunting on horse back and on foot these guns are a bit of a pain to deal with. The Winchester Model 70 and the Remington 700 can be had in rifles of about eight and a half to nine pounds with scope which is about the same as a 7mm mag, or 300 Win mag. So why not carry the latter to take advantage of longer shot opportunities? The last encounter I had with a grizzly I was carrying a Tikka T3 light in 308 and I watched him come up from below to about fifty yards at which point I stood up and made enough noise to let him know I was there. I felt no concern that I did not have a larger rifle, to the contrary, I was in awe of these magnificent animals.
I have been hunting in Montana since 1958 and have carried all sorts of rifles from the Winchester 32-20 up to 458 mag. Most of the time I used my deer rifle which is a 30-06 Remington 7600 with a Williams aperture sight. It is light, fast and feels like my Remington 870 which I use for trap, skeet and sporting clays. I use these guns so often I am confident in my ability to use them effectively.
In the end, you will have to make the decision which rifle you want to use. If you decide to use a thumper I would suggest that you handload your own ammo and do almost all your practice shooting using light bullets to reduce recoil. I have been using Accurate 5744 with good results because it seems to be less position sensitive. On the 375 H&H I like neck resizing for practice rounds to mediate case separation just above the belt caused by stretching. I don't know if The Ruger Guide gun has the same problem since I have never used or loaded for one of these guns. I have experienced poor magazine design which causes feed problems in Winchester Model 70 and Remington 700 in 375 H&H. I have never had a problem with control round feed actions offered by Mauser, Interarms Mark 10, Ruger 77, and CZ 550 Safari Classic.
Once you get your gun fairly well sighted in get off the bench and shoot using positions you are likely to use while hunting. Double rifles have to be regulated so both barrels shoot to the same point of aim. You will not have regulation problems with a bolt gun, but light guns with massive recoil are very hard to shoot well, because the gun is moving from recoil before the bullet leaves the barrel. So don't expect a rifle sighted in using a lead sled to shoot to the same point of aim offhand or sitting. Purchase a low power scope fixed or variable 1 x 4 with a small ocular tube which will not interfere with bolt operation. Make sure you have a long eye relief...or don't and learn the hard way. (Both of my 375 and 458 have peep sights only)
Check Utube for videos of completive shooters shooting across the course. Pay particular attention to how they work the bolt. Learn how to work the bold fast and efficiently in all positions. Keep your gun up when you are working the bolt, don't lower the gun. Shoot, and while still keeping your eye on the game, work the bolt and shoot again if the game is still standing.
A few additional thoughts on hunting. Every year Montana has a few bear incidences, mostly with archers. There is some excellent studies on bear attacks you can get from the Bear Study Center. I suggest you get a copy. What you are looking for are descriptions of places, situations and reasons people get into problems with bears.
Being with a good guide may help keep you out of trouble with bears. If the guide is close to you and either has a gun or pepper spray your chances of getting into trouble is greatly reduced.
You want a guide who will set his pace consistent with yours. Let me repeat that: You don't want your guide scaring off game one hundred yards ahead of you and if you get into problems, too far away to help.
Which guns to I recommend: 375H&H Plenty of power, recoil you can handle, a cartridge of shape and length which feeds flawlessly in control round actions, but most of the time I just use my Remington 7600 in 30-06. Have no fear.
Hope this helps.
