For a real history find Bob Hagels article in Handloader/Rifle. It is in the big compendium book also. I make my cases from .300 Win Mag; original parent was .300 H&H. Neck down and move the shoulder back then fire form. Total case capacity is about 90 grains of water with a long neck that lets you keep .02 clearance off the lands while changing between 150, 160, and 175's. From what I can tell it has about ideal case capacity for a 7 mm hole. Very similar to the 7 mm Dakota without the availabilty problems and what the 7 Rem should have been.
If you build one make sure it is throated for an OAL of about 3.56" so you get all the case capacity. With 175's and RL-25, IMR 7828, or Retumbo you should be able to turn 3050 +/- with safe pressures in a 24" tube. Over 3200 fps with a 160.
In reality it is a .30 mag without the recoil or weight. Mine weighs 7.5 lbs. all up with a #3 Shilen tube. If you can't kill anything short of Cape Buffalo, Rhino, and Elephant with a 7 mm 175 at 3050 fps then we all need to stop hunting.
Warren Page was the master with this cartridge. He killed something north of 450 animals with his.
