Mt^boy-To start with the barnes x and failsafe are not available in 220gr in .308".Either of these bullets in 7mm will outpenetrate the 220gr bullets that are available in .308". Due to their construction they penetrate a great deal more than partitions or similar bullets(up to 50% more in most cases).Secondly the sectional density of the 175gr barnes x(heaviest in 7mm) is higher than the 200gr barnes x(heaviest in .308"
which will result in better penetration from the 7mm.Thirdly the heavier .308" bullet will be travelling much slower than the 7mm bullet so it will not have more inertia than the 7mm bullet.The heavier bullet(of equal construction) must have the same speed and sectional density to penetrate more.(my years in engineering have taught me the concept of dynamics and have shown me that inertia is dependant on both speed and mass)So in your own words get it right.As for not having seen big bears I have seen many grizzlies in the coast mountains of B.C. and have a nice grizzly rug in my den from a hunt a few years back.
Edited by - stubblejumper on 12/01/2002 22:23:52