Forster Headspace Gauge 223 GO 5.56 NATO MIN

The GO gauge is used to measure the minimum allowable, safe chamber headspace. If the bolt does not close on a GO gauge, it is considered unsafe. Must have for rechamber jobs to set the new headspace or to verify the correct headspace of a new barrel and bolt combination. These days, I see a lot more new barrel and bolt combos fail the GO gauge than anything. Failing the GO gauge indicates the headspace is too tight, which increases chamber pressure and failure to go all the way in battery. This leads to pierced and popped primers that will damage the firing pin tip and cause slam fires. It also can cause hard extraction and damage to case heads. The GO gauge should be used to test any new barrel and bolt combination or when swapping in a new or used bolt. This gauge ships only in the USA, No export or APO/FPO.