i have only faced a griz and her cub once on a narrow trail to clear cut.My friend had a 308 win and i had a 7Rem Mag, this was 19 yrs ago. We were 40-50ft from them when they popped out of the brush, i whispered head shots only as the scope was full of the sow bears head. we waited them out and after some chomping licking the air and standing on tippy toes they went their way. The next season we had 338 winchesters with 250gr bullets and feeling a little better when walking. After thinking about it, i do not rush down a trail at dusk anymore, I leave time to walk slowly and observe my surroundings on the way to the hunting spot. Short , light, big bore, scoped down to 1.5 or 2x, slick functioning rifle is what will see you through these encounters, plus learning not to shoot unless absolutely neccessary as all hell breaks loose when you pull that trigger. A 35 whelen is good for this activity as are the various 9.3's. 375 HH generally need to be modified to foefill this function. Whn on the ground i like a good medium , when traveling from place to place a 3006 is good as well as for November deer hunting as the bears have gone to sleep. Your experience may vary.