Many years ago I got a copy of a study done by the US Dept of Agriculture re bear defense for work crews in Alaska. Good read and well done.
Dug up an URL for it:
http://www.treesearch.fs.fed.us/pubs/5573
THIS COULD BE THE END OF THE NEVER ENDING BEAR DEFENSE threads.
Top score was 458 Win Mag
Highest penetration was 45 70 out of a Marlin with 300 Grn bullets...24 inches!!
1 458
2 460
3 375 H&H 300 GR with long barrel
4 338 WIN MAG 260 GR with short barrel
5 375 H&H 270 GR with long barrel
6 338 WIN MAG 200 GR with short barrel
7 338 WIN MAG 250 GR with short barrel
8 338 WIN MAG 200 GR with long barrel
9 338 WIN MAG 300 GR with long barrel
10 375 H&H 300 GR with short barrel
11 30-06 220 GR
12 30-06 180 GR
13 444
14 358
15 7 MAG
16 375 H&H 270 GR with short barrel
17 45-70 300 GR with short barrel
18 308 180GR
19 45-70 300 GR with LONG barrel
"In our tests the 12 gauge rifled slug did not have a high overall rank because of the relatively low striking energy and the lack of bullet expansion."
"We also tested the penetration of 00 buckshot.
...the 9 pellets had a spread of of about 12 X12 inches and a penetration of only 2 to 3 inches. We then shortened the range to 15 feet. From this distance the spread was 2 inches and the maximum penetration of a single shot was 7 inches. At the shorter range the nine pellets appear to act as a single projectile and the 00 buckshot might be relatively effective."
"From our tests it would appear the slug is much superior to buckshot...
Whether buckshot would be lethal beyond 5 yds is doubtful."
"Hitting a brown bear with buckshot beyond 5 yards may mean a nonlethal wound and a very active, angry bear."
"
Hitting vital areas is the important thing"
The moral of the story is a rifle is better with heavy hard nose bullets and
you have to hit it where it will do some damage.
bg