In my FN Mauser I'm using 56.0 grs with the same powder and bullet,different primer,it's a CCI 250 and it's getting almost 2900 fps with a 22" barrel.
Every load I shoot is over a chronograph. For instance,the .338 RUM I have,I wanted 3000 fps with a 250 gr bullet. So,I start with H-1000 and 250 gr Sierra GK's. Looking in the Sierra manual I start with this load 97.0,98.0 and finally the book max 99.0. Used Rem 9 1/2 Mag primers. The very first 3 shots averaged 3001 fps,the max is 3000 fps. So,what I did is go home and pulled the others,because the next loads were going to be over the max in pressure.
BSA,the chrono is your best friend,it'll tell you if you can add powder or if you have too much.
