I have many discusions with D Lazer, master Alaskan guide. He has been involved in over 300 brown/grizzly kills. The most jams have come from M70 winchesers and mausers. Remingtons and the tang safety Ruger M77's have been the most reliable. His back up rifle is a tang safety M77 30-06 loaded with 220 gr factory.
Lefty C
I worked for Dave one sheep season in 1980 and have been guiding ever since. I see him from time to time on the Alaska peninsula and although he is active I don't think the AK F&G records will show that he has anywhere near 300 bear kills. He does still use his old 30-06 but is not all that knowledgeable about rifles.
