The Forster Rimmed and Belted Headspace Gauge in .257 Roberts GO (brand part no. HG0257G) helps gunsmiths and handloaders confirm that a .257 Roberts chamber is cut within safe SAAMI tolerances. Headspace is the distance between the face of the breech and the base of a chambered cartridge, and it is one of the most safety-critical measurements on any rifle. Excessive headspace lets brass stretch or rupture on firing, which can send gas blasting rearward toward the shooter, so gunsmiths rely on precision gauges rather than guesswork to verify a chamber is cut correctly. Forster gauges are made to painstaking manufacturing standards to keep that test accurate.

Key Specifications

• Ground as a GO gauge, confirming the chamber will safely accept SAAMI-spec .257 Roberts ammunition.
• Precision length of 1.794 inches for a repeatable, accurate check.
• Supplied as a single gauge sized specifically for rimmed and belted .257 Roberts chambers.
• Weighs approximately 0.1 pounds, light enough to carry in a range bag or tool kit.

Frequently Asked Questions

What does it mean if the bolt closes on this GO gauge? If the rifle’s bolt closes on a GO gauge, the chamber will safely accept ammunition built to SAAMI industry-standard dimensions. If the bolt closes on a NO-GO gauge, the chamber may already have excessive headspace, and if it closes on a FIELD gauge the chamber is dangerously close to, or already beyond, the maximum SAAMI-specified size. Most gunsmiths aim to keep a chamber cut somewhere between the GO and NO-GO dimensions.

Should I also own a NO-GO or FIELD gauge? Many gunsmiths use the GO gauge alongside a NO-GO or FIELD gauge to bracket a chamber’s exact headspace rather than relying on one dimension alone.

Buy the Forster Rimmed and Belted Headspace Gauge, .257 Roberts GO

Confirm a .257 Roberts chamber is safe to fire before you ever load a round. Find this gauge in our reloading equipment selection, and our Lubbock, Texas team will ship it out quickly.