I did some research on this last year when a friend of mine was planning a trip to Alaska. She handles her 4053 very well but I felt the 40 S&W was on the weak side so offered to let her use my 1006 with some hot handloads. From what I was able to find on the internet, there were a number of opinions that an "original" type 10mm loading with heavy non-hp bullets would be OK for most Alaskan bears, maybe minimal for the really big coastal ones. She shot the 1006 well enough, but decided it was too heavy, plus was not as practiced with its TDA, and ended up taking the 4053 anyway. So I made up some hot 40 S&W cast bullet loads for it with the idea that any gun was better than no gun and she was already very familiar with using her DAO gun in case it was needed. Fortunately she did not need it despite one very close bear "suprise" that was a high pucker factor moment indeed.

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" I said, good DAY! "