cometpx4, the Supremes penetrate very well because their velocity from a 351, combined with their sold construction, does not cause a lot of expansion. At rifle velocities, they expand just fine.
My tests show that from a 351, nothing comes close to the penetration of Supremes. Win. Super X 40 Gr FMJs, Rem. Premier 33 Gr poly tips, and Maxi Mag + P 30 Gr HPs are tied in a distant second group. Maxi Mag 40 Gr HPs are not very far behind that second-place group.
Remember, we are talking about penetration only, and then only at the relatively low velocities from a 351.
Energy dump is a different matter. Even the cheaper, slower, good old Win. Dynapoints expand and dump energy well, but at the cost of about 43% less penetration than Supremes.
I like deep penetrating, bone breaking Supremes for carry (rabid critters/wild dog size protection), although Maxi Mag 40 Gr HPs might be the best compromise (energy and penetration) for a carry round.
Just my two cents based on a lot of testing with phone books. ( A friend delivered phone books a few years ago and had almost 100 books left over.
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