I usually use 78.0gr of W760 with a 300gr bullet in my .375HH to get 2500fps. With the construction of the Northfork I loaded down to 76.0gr to begin with and average velocity was 2400fps. I increased to 78.0gr and velocity was 2430fps. Am I not going to get this bullet to 2500fps with W760???? Pressure seemed to be ok but don't see adding more powder since northforks usually take less powder to reach the right velocity. Anyone shot this bullet that can give some ideas?

Try H-414 (76gr with a 300gr A Frame yields 2580 fps in my Model 70) or RL-15 & 4064.

I have to lower mine 2 grains with NF compared to Hornadys, so not much help with this one. I'd up the charge until I hit 2500 fps.

I obtained some very good groups with 65.5 grains of H4895, just yeasterday. Haven't shot it through a chrony yet. I hope to do so this week. I found that all of the lowest charge weights listed in the Speer manual are compressed loads with Northforks and the accuracy suffered.
The H4895 load is from the Nosler book. Guns used was a m70 with a 22" bbl.