You have the best bullets and powder available for the 308. I use benchrest primers for my match grade 308 handloads. You will find your greatest accuracy will be between 44-46 grains depending on your rifle and pressure signs.
For OAL, First, I start out with a dummy round with the bullet seated out to fit the magazine, then I smoke the bullet with a candle and chamber. If it doesn't chamber, or you get land marks on the smoked bullet, I seat the bullet deeper and repeat. I keep going until the bullet is just off the lands.
I then mark the cartridge with the bullet, rifle, and seating depth and keep that round for that bullet, and that rifle as a gage for setting up my die just in case I have to move the seating stem for a different bullet.
It's old school, but it works.
Callawegian STITCHERY