atkinson,
I know about sectional density but what about JPK's contention that the flat point shape of 450 grain North Forks creates an effect that lets them penetrate deeper than Kynoch-shaped 500 grain round noses which have better sectional density? In other posts, JPK has actually shot animals with North Forks to prove this, IIRC. Also, there have been some theoretical studies about this posted on various boards, though personally I trust the people who have used them better than the theoretical studies.
Irrespective of shape, the sectional density of the 450 is over 300 and I can get 2250 fps with no pressure problems. From what I have read, that should put my .458 easily into the DG range.
The 450 grain .458 bullet has slightly better sectional density than does the 300 grain .375, slightly lower velocity, and 50% more weight; also slightly less sectional density than the 400 grain .416. What's wrong with that?
The only problem is that North Fork went out of business. I only have 44 of these solids left. Fortunately, I have the load worked up and I keep very thorough notes. The North Forks shoot 1.0" lower than 450 grain TSXs in my rifle at 100 yards, so I don't even have to waste any confirming my zero. 44 might last many years.
