Brownells Tech Tip: AR-15 Headspace

Bought a brand new AR and then went out and bought an upgraded bolt, is a headspace required?

So my .223 wylde barrel is brand new from CMC. I have checked bolt and the barrel and the barrel seems to have a bit of a spacing issue when testing it with the go gauge, it doesnt close flush. Could this be the finisher coating? I dont want to fire it if its going to explode on mez

So a factory assembled upper doesn’t need to have the head space check, even if the bcg was ordered separately both from same manufacturer?

The explanation of the “Colt” gauge is a little confusing. I think they are referring to a 5.56 max gauge which would be used for any NATO 5.56 chamber (as opposed to .223) …not just Colt. Colt is the technically the spec for 5.56 but many other companies chamber for true 5.56 (BCM, LMT, etc)

I've got a question. I'm beginning to start reloading. Can I just start off by setting my sizing die to flush, or slightly backed out, and check the brass in the chamber, to see if the headspace is correct? And then, if it isn't, slightly start screwing the die down, until it's perfect? This will simply bump the shoulder back to an exact dimension, without causing excessive headspace. From what I understand, each chamber is gonna be slightly different, as far as headspace dimensions. So, it wouldn't even do any good to check your case with a headspace gauge, because YOUR specific chamber may be a little shorter, or longer than the standard gauge. I hope this makes sense, and I would REALLY appreciate your opinion on this. Thanks.

What is the fix if it closes on the no-go gauge ??

When using a head space gauge, NEVER let the action slam shut on the gauge, you can easily jam the bolt /BCG where the chamber was just a little too small for the gauge and now it may be near impossible to get it out! Only use your thumb to push the bolt carrier forward! Saw it happen!

Thanks for the info.

Since your website won't let me leave a review about one of your products I'll leave it here.

I just returned one of your Brownells brand NiB lightweight BCGs that failed a no go gauge. 1-star, BUYER BEWARE!

Question – I bought 2 complete uppers from your company. I'm curious if you check the headspace before shipping?

What size punch or roll pin did you use to get the pins out of the bolt?

Don't use 1/16th…it goes right through the middle of the pins and jams in there, and I think by bolt is trashed b/c of it. Grrr.

I have a .223 Wylde barrel..can I use either 5.56 or .223 gauges to check the headspace?

What gauges do you use if you have a .223 Wylde barrel or a ar-15 lower receiver marked 556/223? Want to buy the correct gauges.

Question regarding headspace on a AeroPrecision M5 Build:

Yesterday I swapped out barrels on my M5E1 and put on a Ballistic Advantage 20" 308 Bull Barrel. I checked headspace with Forester Go & NoGo Gauges. The interesting part is when I checked the headspace with the barrel out of the upper, both gauges worked as expected indicating headspace is safe. However when I assembled the upper, I put the NoGo gauge in and the bolt closed completely on the NoGo gauge. Wondering if anyone has experienced this before. The assembled upper method with the NoGo gauge forcing the bolt to stay out of battery is what I saw on Brownell's tutorial section.

Would you guys say the rifle is safe to shoot considering headspace gauges passed the test with the barrel removed?

Thanks,
B

Too Brownells has stopped providing the great gunsmithing tools they used to sell. now it's almost all for 1911 or ar's no more plating supplies drilling fixtures etc. Hope Midway will pick up the slack.

could not find the gauges at Brownells what is the part #

I wish I wasn't so impatient. All I wanna do is go to the range with my self-built AR!
Guess I should check the head-spacing first! Got the gauges and ready to go.
Thanks Brownells.

Hello, I have an upper that uses the Pantheon Arms Dolos kit (barrel quick change system). I use the upper between a .50 beowulf barrel and a .300 AAC Blackout barrel. I think the Blackout barrel might not be head spaced correctly since it didn't come with its own bolt and I was just using my regular 5.56 bolt with it. It's slightly crimping one side of the lip of the casings after ejection. What can I do if it is a head space issue? I have several other 5.56 bolts, should I just try the other bolts? If none of the other bolts perform better, what would a gunsmith do to fix the issue?

so if i have changed my upper but not my bolt or barrel would i need to check head-space or should that still be the same?

what kind of reading does get if the bolt is not fully disassembled? say you only removed the extractor and then performed the test? can the resistance from the ejector give a false reading?

this is a great video but it leaves to question, why isn't this process done on the production lines when the barrels are produced? it seems like this process could potentially save a lot of time and aggravation having to return and wait for replacement barrel or pay a gun smith to fix headspacing.

just ordered a pair of gauges last night 🙂

Please start listing part numbers.

Great information here from Brownells……thanks for all your videos..!

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