I'd build an 8 or 7 twisted .223. #3ish contour finished @ 20". No more than a 1" shank.
Make sure you know what your limit is going to be for COAL. Seat some dummy cartridges accordingly and make sure the smith understands why you are including them in the box.
DBM's can limit COAL, they can also increase COAL. Depends what we're going to use on the build.
If this is going to be primarily a range toy and hunting from a blind, I'd not hesitate to go heavy as fugk on the barrel and put it in an A5. Just a thought.
I wouldn't look past a 10X Super Sniper for glass. Maybe the 3-9X HD if you want a variable.
Travis
