Hi,
In my rifle (cz Fox ,30/221 PTG chamber), I am loading 16.5 grains of N110 behind the 125 gr nosler BT. The COAL is 2.180 and I get 2340 fps in a 16" barrel.
More powder and I start to see sign of pressure on my cases.
Again, start at 15 grains and go up progressively.
Good Luck
ND