Originally Posted by
JohnDuxbury
You should use 7mm08 data for your 7x 57 reloading. (Ignore the 7x57 loads in books, much too low pressures; to accomodate the ancient Remington Rolling blocks that might be floating aorund...)
I use 2209 in my 7x57 and with this powder you can safely load 120 bullets up to 3100 fps with a 24 inch barrel and 140 bullets up to 2900 fps. You wont get exactly the same result as the 7mm08 data because the 7x57 has around 8% more case capacity, so its a slightly less pressure for the same load data as a 7mm08, plus the 7x57 sometimes have much longer throats and you may not be able to touch the lands with your bullets. This means you have to add more powder to get the same velocities, (and therefor the same pressures.)
I would start with 50 grains of 2209 and a 140 grain bullet: stop putting powder in once you chronograph 2800-2850 with your 22 inch barrel.
As for the twist rate, dont worry about it, even a slow twist 1:8 will shoot 140 grain bullets well. Seat the bullet so its just touching the lands, or as far out as you reasonably can. You may or may not have a long
throat on that rifle, the old Ruger tang safeties did, the Brno's do, but my Remington doesn't.
As for brass rim sizes - Sellier and Bellot brass will not fit a Lee shell holder, and UUY Highland did not in the past.....but now the stuff sold as Prvi Partisan with the PPU headstamp fits fine. As you have found out, US brass fits okay if you can find some.
(Out of interest I have made 7x57 brass from .30/06...I have a lot of '06 around. And I have time. So you run your lubed '06 case into the 7x57 die, and then you have to cut some of the excess neck off with a little pipe cutter, (or a hacksaw) and then you trim can it to size.)