To be fair, the Speer Manual #15 compares both in 24-inch barrels and arrives at essentially the same MV with 175-grain bullets, but using different powders for each. When they list top loads for both with Reloader 19 powder, the 7mm-08 gets 2,628 fps with 47 grains powder, the 7×57 hits 2,529 fps with 48 grains. HOWEVER, the Speer manual warns users: “DO NOT EXCEED STARTING LOADS LISTED IN THIS MANUAL” if shooting the ammo in Spanish Model 1893 or 1895 Mauser actions. Those starting loads equal the velocities of American-made 7×57 Mauser ammo. So in factory loads the 7mm-08 Rem. does have a velocity advantage. At the same time, however, it’s nearly impossible to find a 7mm-08 factory load carrying a bullet heavier than 150-grains. I’ve found 7×57 Mauser ammo fitted with 156-, 158-, 162-, 173- and 175 grain bullets. Factory 7mm-08s seem to come with 120-, 139-, 140-, and 150-grain bullets only. But something new could pop at any time.
Here, then, are some 7mm-08 Remington ballistics with the same 175-grain bullet we used in the Mauser. The Hornady reloading guide, 10th edition, shows a top load of 45.9 grains H414 reaching 2,600 fps MV from a 24-inch barrel, a crazy, 300 fps advantage over the Mauser. But, once again, the Mauser loads were measured out of a 22-inch barrel, so, figuring an average 25 fps per inch of barrel velocity change, we’ll drop our 7mm-08 load to 2,550 fps. Here are the results:
7mm-08, 175-gr. Hornady ELD-X Trajectory Table
7mm-08 Remington vs. 7×57 Mauser & 7mm Remington Magnum — Ron Spomer Outdoors is written by Ron Spomer for www.ronspomeroutdoors.com