Hells Canyon Armory heavy hunter contour but with the ultralight core. 20" finish 7.75 twist. Bbl weighs 2lbs 12 ounces and .860" at the muzzle. Will stabilize a 135 hybrid at sea level with SST,PRC, or Saum velocities. Had this bbl on order for over a year before it was available and was able to get my project going sooner by going to an IBI bbl. $810 shipped