Not knowing the chamber depth of your rifle, it is difficult to give you a specific answer, but this might help.
Federal Premium factory ammo is rated at 2650 fps muzzle velocity but that is measured in a test barrel not in your rifle. Also, the factory ammo is seated out at 2.800 COAL +/- 0.004 inches from my measurements.
That said, you need to use that velocity data and COAL as variables when you try to duplicate the results with the factory ammo.
I have bettered Federal Gold Match SMK ammo results with either Reloader 15 or H4895 powders with the 168 Sierra Match King bullet, using about 5 different kinds of brass (head stamps not varied for any particular experiment) & Federal 410M match primers.
If you load from the Sierra manual in 25 fps increments from 2625 fps to 2675 fps and vary the COAL from 2.800 to 2.815 in 0.005 increments, I think you should find a very accurate load for your particular rifle that will better the factory ammo.
Using the same powders, I have gotten equal results with Nosler Custom Competition bulltet seated about 0.010 than the best loads with the Sierra SMKs.