Thank you Ridgewalker,
Bullet sectional density is simply a product of the mass of the bullet divided by its cross sectional area. The cross sectional area, when comparing 375 H&H to 375 H&H is constant. It would stand to reason a 300 grain bullet would have a greater sectional density than a 270 grain bullet because truly, what we are talking about in the 300 grain bullet is a bullet that is heavier...by 30 grains. We've come full circle.
All things being equal and assuming we're squeezing what we can out of the cartridge, the 270 grain bullet is moving with higher velocity. If it holds together, as the monolithic bullets tend to, I'd guess penetration would be better with the 270 grain bullet travelling the same path through the game animal.
As we all know, these arguments have been going on for as long as people have built metal tubes and stuffed powder and lead into them. My point was I find it interesting how absolutely convinced some folks are that 30 grains (traveling slower) make that much difference for an animal that weighs 2000 lbs.
The real question I had was about the Hornady CX and what people thought. Honestly, I'm a huge fan of Barnes bullets, but they are very difficult to find. Midway is constantly sold out of 375 caliber in Barnes and 130 grain 270 caliber LRX bullets as well. Very frustrating and I'm not sure why Barnes does not crank up production a bit to meet obvious demand. The 250 grain Hornady CX bullet looked to be very similar, so I thought I'd give it a try.