I would stick with the Nightforce for the now. That scope is tough as nails and it's bore will never shoot out. See where I am going with this?
Stick it out with the 300 ultra, add a muzzlebreak and make sure you have good bedding. In the mean time keep saving your nickles for that custom rifle.
BTW, once your brother has spent all those nickles on his 7mm, you better keep a close eye on your nightforce - it might end up on his rifle if you turn your back!
That's what my brother would do!