Every gunsmith understands that the correct application of a headspace gauge is the most dependable method for assessing the length of a rifle chamber. Headspace refers to the distance between the breech face and the base of the cartridge when the action is closed. Excessive headspace can pose safety risks and compromise accuracy. For example, unsupported brass fired in a rifle action with excessive headspace may rupture, causing gas to escape rearward in a manner similar to rocket exhaust. Given the critical importance of safety, Forster headspace gauges are manufactured with meticulous attention to detail and stringent standards to ensure precise testing of your rifle's chamber. If a rifle closes on a GO gauge, the chamber will accommodate any ammunition produced within SAAMI (industry standard) specifications. Precisely machined to stringent SAAMI specifications, these gauges deliver precise measurements to ensure a firearm's chamber adheres to industry standards A go gauge verifies the minimum chamber dimensions, ensuring that the firearm can safely chamber and discharge a cartridge Constructed from high-grade steel and engineered for durability, these gauges are designed to endure repeated use while maintaining precision