[Stinky Coyote]

All things being equal…same amount of powder burned, diam. of projectile, construction, medium etc. but two different bullet weights (read; two different s.d.’s)…the heavier goes deeper. Why? Really the added offset of the higher velocity of the lighter projectile should match the slower heavier one right? But it seems well known the slower heavier one will go deeper given same diam. and energy.

Efficiency is the answer, there is a relationship between velocity/drag that is exponential. When you try to offset a lesser s.d. with more velocity in the same cartridge (same amount of powder burned/same amount of energy) the higher s.d. goes deeper because of that exponential drag to velocity relationship. In order to to equal the more efficient higher s.d. bullet you have to add a dis-proportionate amount of powder to get the same depth of penetration…jump to the next size up case (standard to magnum so to speak). That simple rule of thumb, faster it goes faster it stops, slower it goes slower it stops, can more easily be applied here to understand that. Ie; given same bullet construction, a 30-06 running a 180 gr will likely penetrate as deeply as a 300 win mag running a 150 grain. Which is more efficient? The 30-06 180 gr hands down, your shoulder will confirm it.

This is the draw to high s.d. bullets…efficiency. Another bonus is the higher s.d. bullets are often of much higher b.c. too so less losses on the way to target also, extending range capability. Again, more efficient. It’s win win.
The 6.5 creedmoor and all other 6.5’s are just more efficient in both areas, higher s.d. and b.c. is win win, on way to target, and through the target. It’s more than just marketing hype. Bell’s 1100 elephants mostly killed with 6.5 mannlichers/7x57’s explain so much about the subject around penetration. S.d. is the ultimate figure to use for comparing these things. The new .224 valkyrie running 90+ gr bullets is doing the same thing. Reduce the numbers of all cartridges/bullets to the same and you’ll see what will work for you, what your preferences are that you didn’t even realize.

Using the data available properly allows you to reduce a new cartridge like a .224 valkyrie or 6.5 Grendel or Creedmoor to comparable numbers rather than shoot a bunch of game and then figure out what works and doesn’t. We have the knowns, the data is there. When you crunch it on a new cartridge you can then see what it will compare to that we already know. A 6.5 Grendel will hang with a .243, it will beat it’s s.d. and match it’s impact velocities to the same distance and it will do it with substantially less powder. It’s quite a bit more efficient than the well proven and documented .243 win (in this case you need to burn another 20 grains of powder with the .243 win), the new Valkyrie will be exactly the same or as I’ve been saying plenty…these new cartridges punch way above their proverbial weight.
Forget ft/lbs, forget momentum, forget diam. forget headstamps. Get things reduced down to s.d./impact velocity/construction and you’ll be surprised what cartridges can meet or beat others already known…for distance potentials, and or, penetration potentials.

I know many of you are sick of this, don't read and don't respond. But show me better ways of comparing new cartridges to known, or existing to existing etc. and i'm all ears.

I wouldn't post this if the recorded animal deaths from any of the camps weren't bearing all this out in the real world.