Got my gun back from the smith! My first big bore (ok big-medium)
Dpcd (Tom Jackson) on AccRel, did the work. Its his custom contour, which is based on the "Duke of Marlborough" contour (very similar to a Brit stalker/Rigby highlander). Douglas .410 bbl 1:14 twist. This is the Petrov/G&H/ Original Whelen correct chamber, not the copy cat chamber that got the bad rep for head space issues.
M70 Classic 24" Douglas bbl. It is going to be sent out for cerakote here shortly after I sella few more items.
Dies are in the way. This should throw a 400 gr bullet around 2125-2160, but I think i'll try to find a good load with a North Fork 360 gr bullet, which has an SD of .301 and should easily hit 2250+ for +4000 ft-lbs. Do believe that'll knock a buff down. Those are the same numbers as the 450/400 with the same bullet.
Right now it's wearing a Zeiss Terra 3X 2-7x32 for test fitment and pictures. May move my Leupold 1-4x20 over from my 375 or buy a FX-II 3x20 or Weaver Classic V 1-3×20. Heck may even try out a Weaver Classic 4x32 Ive got sitting around.