The Forster .300 Blackout NO GO Headspace Gage (Forster Products part no. HG0300N) gives handloaders and gunsmiths a precise way to check rifle chamber headspace on the rimless .300 AAC Blackout cartridge. Forster builds every gage to exacting manufacturing standards because a chamber that closes on a NO GO gage may already have excessive headspace, and that is a safety issue, not a convenience one. This gage suits gunsmiths checking new-barrel fit and handloaders verifying their own bolt guns before loading a single round. It is a simple tool that answers a critical safety question with certainty.

Key Specifications

• Machined to a 1.082-inch gage length for accurate NO GO headspace verification on .300 Blackout chambers.
• Classified as a No Go Gauge, meaning a chamber that closes on it may already carry excessive headspace.
• Ships as a single gage per package (quantity 1) for straightforward one-caliber use.
• Weighs a compact 0.05 pounds, small enough to keep in a range bag or gunsmithing kit.

Frequently Asked Questions

What does a NO GO gage tell me? If your rifle’s bolt closes on this gage, the chamber may already be at or beyond the safe headspace limit and should be checked by a gunsmith.

Is this gage caliber-specific? Yes, this gage is machined specifically for the rimless .300 AAC Blackout cartridge and is not interchangeable with other calibers.

Do I need a GO gage as well? Most gunsmiths use GO and NO GO gages together to confirm a chamber falls within SAAMI-acceptable headspace tolerances.

Buy the Forster .300 Blackout NO GO Headspace Gage

Order this gage directly from Forster Products through our gunsmithing tools lineup and add a reliable, SAAMI-accurate check to your reloading bench. Order it from our Lubbock, Texas gun shop for fast, insured shipping.