As others have said, it is tough to compare whole lines because different configurations are built differently.
From what I've been told generally speaking the "heavy for caliber" NBTs are a lot tougher than either the SSTs or their lighter siblings... 150 gr 7mm, 180 gr 30 cal, 180/200 gr 338 cal, etc. That is, they have thicker jackets.
My experience has suggested that each rifle is an entity unto itself and you just never know what it'll like best. I've had excellent results from both bullets accuracy-wise but in different rifles. My '06 LOVES 165 gr SSTs but doesn't shoot the 168 gr NBTs quite as well.
As others have said, I'd go w/ accuracy first. Either one is going to do fine on whitetails no matter the angle. If the 140 NBT works well accuracy-wise stick with it, go forth and fill an ark. If, on the other hand, the 139 SST does best stick w/ that. Let your rifle speak to you !
From what I've been told generally speaking the "heavy for caliber" NBTs are a lot tougher than either the SSTs or their lighter siblings... 150 gr 7mm, 180 gr 30 cal, 180/200 gr 338 cal, etc. That is, they have thicker jackets.
My experience has suggested that each rifle is an entity unto itself and you just never know what it'll like best. I've had excellent results from both bullets accuracy-wise but in different rifles. My '06 LOVES 165 gr SSTs but doesn't shoot the 168 gr NBTs quite as well.
As others have said, I'd go w/ accuracy first. Either one is going to do fine on whitetails no matter the angle. If the 140 NBT works well accuracy-wise stick with it, go forth and fill an ark. If, on the other hand, the 139 SST does best stick w/ that. Let your rifle speak to you !