Tom and Larry both give good advice. We have had some experience with Grizzlies, but always stayed safe by following a number of cautions. First it is their land--and never contest that. Second always be very aware of what is going on. Make noise when going ashore and on the trail. Let the bear know where you are, and what you are doing. If encountered, slowly back away--keep the dogs under control. Keep calm, let the bear identify you as a human, and back away slowly.
If you want to see Grizzlies, then see if you can get a permit for "Pack Creek"--given out at Juneau, on a lottery basis, as well as by reservation. There are a large number of bears feeding and a ranger there. You cannot show up there and expect to go ashore (We did that the first year). You only have 3 days to get from Juneau to Pack Creek.
We had two labs with us the 4 years we cruised SE AK with the Cal 46. They went ashore at least 3 times every 24 hours. Primary defense was bear spray. Although "pepper spray" and "Mace" is illegal in Canada, Bear spray is not. In fact in the Queen Charlotte Islands there are some areas where it is suggested that you have bear spray on your person if ashore. The bear spray range is listed at 32 feet. We have tested an old can of "Counter Assault" and it did spay 30 feet. But the usual effective range is considered at 15 to 20 feet.bout 10 seconds of spray. You have a If a bear is charging--that is mighty close! The bear can run much faster than you can. Our decision if in danger is that Marie would handle the bear spray and if shots were necessary, I would do that. But, a bear will continue even with a .44 mag shot in center mass, head or neck, so a shot is a very poor choice and a last chance--avoidance is best. A shot bear better have powder burns.
We did also carry one of the horns, and if any question, we both yelled before going ashore and hit the horn, especially at night. We also used a spotlight to check out the shoreline at night.
As for firearms--we carried a ..44 Mag with a high cross draw (chauffeurs type) of holster. Load: 300 gr solid bullet, with a "hot" load. This firearm requires a lot of practice shooting to be comfortable and is not for everyone. A shot gun is difficult to carry, as well as handle a dinghy outboard, landing on the beach, dogs on lead etc. It might be easier if you could use a "riot gun"--but not allowed by Canada. (We did not let the dogs off the lead if any question about bears in the area.) The hand gun is not as good as bear protection as a slug in a shot gun. The .44 had to be sent to AK by our fire arms dealer to another fire arms dealer, to avoid the Canada issue.