Re: 1000 yard nikon bdc shot with a .308?
I will echo what BGE 541 stated about turrets being a better option. A 308 is dropping very steeply at 1000 yards. You need to have good data to make reliable hits at that range, not to mention some skills at reading the wind!
What data do you need? Accurate distance most likely via a quality laser range finder or a gps. Density altitude is pressure altitude corrected for non-standard temps. It is the altitude (aka air density) the bullet thinks it is flying (bullets don't actually think, but sometimes I wish they did!). In general terms; hot temps, low pressure, high altitude, and high humidity produce favorable conditions (high DA) for bullet flight with less drop and less lateral deviation secondary to wind. What does this have to do with mil or moa turrets? You can use a cheap ballistic calculator, a kestrel weather meter, and dial the correct hold for the conditions. This will provide much more consistency across a range of environmental conditions, especially at long range. This is the science of shooting! Of course, this only deals with the drop! You still have to figure out where to hold for wind, this is the art of shooting. Wind is really interesting to try and figure out. It is a skill that requires a lot of patience, practice, and preferably with a good spotter.
Short answer, you may make some hits, you will probably not be very consistent. If you make any hits, it will have probably more to do with the skills of your spotter than your shooting.