I have been running 25 SAUM for awhile now, it's awesome! I'm mostly running a PRS friendly load (3175 fps) @500 ft DA, elevation adjustment at 1000y is 5.8 MIL/19.8 MOA
mine is a 24.25" Rock Creek 1:7.75" and I have ran it up to 3285 fps with Hornady brass, with better brass and a longer tube...