A PROOF Research carbon fiber barrel and bolt, specified as .257 caliber, 26-inch length, with a 7.5 twist and 5 groove rifling, in a Sendero profile. The item is contained within its original rectangular corrugated cardboard box, featuring the prominent “PROOF®” logo and the slogan “Carbon Fiber Perfected.™” The box also states “PROUDLY DESIGNED & BUILT IN MONTANA, USA.” A detailed white product label on one end confirms the contents and provides “PART : 114445” and “U.S. Patent NO: 10168117.”









