You are right about H110 / Win 296 (the same powders) It is at its best with full power loads. It is not flexible, but is the right tool for the job, in your situation. I am not familiar with N110, but if you want max velocity in that rifle barrel, then a slow powder like H110 will do it.
I get 1850 fps with 240 jacketed bullets and Win 296 / H110 powder in my Marlins. Never tried loading the 210 sierra for use in a rifle, but don't see any reason you cant get 1900 fps plus out of yours.
Question - When using reloads, how do the "powers that be" know your velocity?
Larry