Welcome to the forum.
As mentioned, 3.340" is the SAAMI spec. You might be able to load longer in your rifle. I always try to get .015-.020" off the lands but keep in mind that you have to be able to load into the magazine.
ive got the blind mag. so length isnt a big deal,, i understand about the varying lengths for the rifle,, i was just wondering what nosler recomended for seating deapth on there bullets.