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5.56 mm NATO
Field Gauge
Product no.: 319418033
757253992421 Made to the Colt factory's special dimensions for M16/AR-15 rifles. It measures the maximum factory acceptable headspace; an essential check on guns that have seen extensive service or have been rebarreled.Delivery time approx. 7-14 days.
The 5.56MM Maximum Headspace Gauge from BROWNELLS is designed to meet the Colt factory's precise dimensions for M16/AR-15 rifles. This gauge measures the maximum factory acceptable headspace, making it an essential tool for checking firearms that have undergone extensive service or rebarreling.
Using this headspace gauge is crucial for maintaining the safety and performance of your firearm. Regular checks can prevent potential malfunctions and ensure your rifle operates reliably.
5.56 mm NATO
Field Gauge
Does its job, extra security 18/03/2014
I purchased this to verify the headspace in my AR build did not exceed spec as I built the upper from individual parts. It checked out fine and shot fine as I figured it would. However, 22 bucks is a small amount to verify safety. Sure, you could just shoot it and make sure the cases arn't bulging or the primer backing out. Still worth it to me and it was nice to verify everything was indeed mil-spec. This should be a do it yourself job for anyone that can successfully build their own AR, just a matter of stripping the bolt.
A must have for the AR-15 owner 16/07/2012
I bought this gauge to know without a doubt that my rifle would be safe to fire and free of any factory defects in headspace. This gauge is also a must have for any AR-15 shooter who wants to replace a bolt or buy a different bolt than what was originally supplied by the manufacturer of the upper receiver.
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