What is the ideal lenght for a .223 Rem 700 ADL Varmint .820 barrel contour with a 1:9 twist ??? The gun is brand new has never been fired in box. Have had it a several of years now. It seems was a spec run for Dick's, most 223's are 1:12. Got it on a black friday sale for $359. I have to set it up with a Nikon Monararch UDC 3x9x40 for hunting. The trigger has been tuned to a sweet 2.25 lb. and rifling mildly hand lapped. Shots at game can vary from 25 to 450 yd. The long barrel is cumbersome for eastern NC pine woods/swamp and cut-down hunting but do not want to give-up ballisticly. gun)I plan on hand loading after a short break-in.