Brownells Chamber Hone Features The Brownells .223 Remington Chamber Hone uses 800 grit silicon carbide abrasive balls on a twisted steel shaft designed specifically for the 8 inch shank length required by .223/5.56 chambers. As the hone flexes and conforms to the chamber s shape it polishes away fine roughness left behind after a coarser hone or factory reaming process. This finer grit produces a smoother finish that reduces friction on the case during extraction which is especially valuable in semi-auto rifles that cycle quickly. The improved surface finish translates directly into more consistent reliable extraction under repeated firing. Brownells specifies that the hone must be used with Flex Hone oil to protect the chamber surface and allow the abrasive to work as intended and instructions are included for a simple at-home process. This hone rounds out a maintenance routine for .223 Remington rifles that have already had rough spots addressed with a coarser grit. AR-platform shooters and precision rifle owners alike can use this tool to fine-tune extraction reliability without gunsmithing equipment. It is a low-cost way to extract the last bit of smoothness from a chamber. Brownells Chamber Flex Hone Specifications Brand: Brownells Style: Rifle Hone Caliber: .223 Rem Grit: 800 Available At: GrabAGun