The Forster 30-40 Krag Field Gauge (brand part no. BG3040F) is a precision steel headspace gauge sized for the 30-40 Krag chambering found in vintage Krag-Jorgensen rifles. Forster Products machines it to a fixed 1.19-inch length representing the maximum service-limit headspace; if the bolt closes on this gauge, the chamber has worn beyond a safe working tolerance and the rifle warrants a closer inspection before more rounds are fired. Given the age of most Krag actions still in circulation, a field check like this is a reasonable step before putting an older rifle back into regular use. It pairs well with the rest of our gunsmithing tools and gunsmith supplies for anyone servicing period rifles.

Key Specifications

• 30-40 Krag Chambering Ground specifically to the 30-40 Krag cartridge’s headspace dimension.
• Field Gauge Type Represents the maximum acceptable headspace for a rifle already in service, flagging excess wear.
• 1.19-Inch Gauge Length A fixed, precision-ground reference length for a consistent go/no-go style reading.
• Steel Construction Hardened steel built to retain its exact dimension over repeated use.
• Single-Piece Gauge Sold individually for the field-check step of a headspace inspection.

Frequently Asked Questions

Why check headspace on an old Krag rifle specifically? Older military and sporting rifles that have seen decades of use are more likely to have chambers that have worn beyond factory spec, making a field check a sensible precaution.

What’s the next step if the bolt closes on this gauge? Have the rifle inspected by a qualified gunsmith before firing it again; excess headspace can affect case life and safety margins.

Buy the Forster 30-40 Krag Field Gauge, Steel

A vintage Krag deserves a proper check before it goes back into rotation. Order this field gauge from our Lubbock, Texas gun shop for fast, insured shipping to your bench.