The Forster Inside Neck Reamer is precision-engineered for .284 bullet diameter applications with exact specifications of .286-.2865 inches for optimal case neck preparation.Forster Inside Neck Reamer Model NR1284.284 bullet diameter with .286-.2865 precision rangeMounts in Case Trimmer for accurate brass removalEliminates excess brass from case neck wallsPrevents chamber pressure and flyer issuesGrinds entire bullet diameter for perfect symmetryMade from strong and durable steel constructionDesigned for unsized and untrimmed fired casesEssential for serious reloaders who demand precision and consistency this neck reamer ensures proper case neck thickness to prevent chamber pressure problems and improve accuracy in .284 caliber ammunition preparation.