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Hello fellow Calgunners. I just put together my first AR upper and have a question. How do I check headspace? I used a mega monolithic upper with a mega lower, a 16" white oak barrel and a DPMS BCG. Is head space even required? Any info would be much appreciated.
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Those who trade liberty for security have neither. ~John Adams -
The headspace was set by White Oak when John installed the extension on the barrel.Frank
One rifle, one planet, Holland's 375
Life Member NRA, CRPA and SAF -
AR type rifles when building them, are a go or a no-go. After the rifle is together, if the bolt locks into battery, then you are good. If it does not, it never will, and you probably have a worthless barrel on your hands. Down the road, and the weapon wears (bolt lugs etc), headspace may grow. At this point, you may eventually want a "field" gauge, which is the maximum amount of headspace without risking a dangerous situation. If the field gauge closes with the bolt into battery, then you have too much headspace, and it would be dangerous to fire.
FYI: I have heard some field gauges require removal of your ejector and/or extractor to get proper seating. Read the instructions if you buy a field gauge, make sure you are using it as it was intended.NRA Benefactor Member
SAF Life Member
CGF Supporter
CAL-FFL Member
Firearms Policy Coalition SupporterComment
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Thank you both for the info!
Those who trade liberty for security have neither. ~John AdamsComment
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