Originally Posted by
super_hunt54
Been trying to wrap my head around that myself. Same weight bullet+ LESS case capacity= slower no matter how I try the math. I get around 3000fps with 139gr Interlocks out of my 24 inch barreled AR10 7mm-08 and around 3050 out of my 28 inch barreled pro hunter. Both of those loads are around 102-103% load density without being compressed. It's impossible for me to figure out how you are getting the same speeds with the same bullet weight and 20% LESS case capacity. Even using that super fast leverevolution powder just MAY get you to 2600fps but that's a heavy MAY! I personally think someone is fudging some numbers somewhere.
I've wondered about that when I compare the Hodgdon number for the 25 WSSM to the 25-06 Rem. With a 117 gr bullet from a 24" bbl the WSSM has almost identical velocity to the 25-06 using 10% less powder (4831) But pressures are 15% higher. I assume it's because of the compressed load in the 25WSSM.