AR-15 – Properly Check Headspace (Uninstalled Barrel)

All you need is a field gauge and a live round

Is this necessary when installing a new barrel?

So even new barrels can have a bad headspace?

So no need to remove ejector and extractor?

I have a DPMS with a carry handle want to change to flat top do I need to check head space? Thanks

Very simple.
Very straightforward.
Thank you.

No long BS just getting to the point. Love it and I subscribed. Keep em coming. Starting my new build on a 6.5 Grendel and need some intel before starting.

so there is no need to check headspace AFTER the barrel is installed?

by chance could you do this with a spent case??

Will this only work on 556 barrels?
Or will it work on 223 wylde as well?

call me ignorant but I have completed A LOT of builds and if you use well built bolts and barrels (the only things that matter) head spacing isn't that critical. normally u will have under 2 thousands

That's a much better technique.
Thank you.

you don't need to manufacture already did that for you

every build should be headspaced, it's just good practice. also, you should always use a stripped bolt so as not to get false readings. if the bolt won't close on the go gauge & a different bolt doesn't help, then u can either return the barrel or ream it. too much space & the barrel extension must be removed & the breach must be faced.

so testing it with method, do you need to take parts off of the bolt like you did in the other video, or can you just leave the bolt fully assembled?

Ive heard the barrel must be installed to "properly" check the headspace

question: if you're doing your own build from the ground up, and you check the head space prior to assembling your upper, do you have to check it again after it's assembled, or is that a redundancy that isn't necessary?? please excuse me if that's a dumb question, but i'm in the information gathering phases of my build and haven't actually ordered any upper parts yet. thanks, and thumbs up 🙂

5000 videos on how to check the headspace, but not 1 that tells you what to do if it is out of spec.
I do not see any way of adjusting the headspace on an AR like you can on an AK.
I guess it is bolt or barrel replacement rather than any kind of adjustment?

Great video, seems simple enough. Question, what happens if the test fails. Whats the adjustment? taking material off the back of the bolt lugs? Replacing the bolt?

I thought checking headspace properly, was done without the extractor and ejector installed…

Short, sweet, to the point, and accurate. Well done!

Thanks for posting this video.  I am building my first AR15, so I am still learning. 
Where can I buy a set of GO/NO-GO gauges?

I'll have to take a drive up to see Dale  THX

On your other video with an assembled upper, you remove the extractor and ejector. Any issues of not doing it with an unassembled barrel?

Suppose you check it with the go gauge and it doesn't move as much, how do adjust the headspace?

Dynamite videos! Thank you for the professionalism and selflessness by which you share your knowledge.
A question was asked regarding the importance of headspace , something to the effect of 'why do I need to check it anyway? As a retired 1SG , US Army I am extremely glad to see that there are so many Americans taking an active interest in firearms, up to and including assembling their own. I have to admit though that that question, or should I say that lack of kbowledge is a little concerning. No way is this the fault of the person who asked. Instead I would say 'Outstanding!' that the knowledge is being sought out.
Here is the easiest and best explaination for anyone interested short of attending the Master Gunner course after enlistment and the things leading up to getting there.
Go to. Thecmp.org/Training-tech/armorers-corner/headspace
It explains in the easiesr way I've found so far regarding what headspace is. As far as firing any firearm with the headspace out of tolerance, simply put it can lead to a catastrophic failure and possibly your (or your buddys) life.
The only dumb question is the one not asked.

I got a problem, I was firing my AR-15 today, and the shell didn't eject once I shot, causing the other to chamber and pushing the casing into the barrel. Now the casing is stuck into the opening of the barrel. How can I take it out?

So much simpler than other methods I've seen. Excellent explanation!

I think I got, but a new quality bolt and a new barrel should be milled to specs and checked before leaving the factory. If you change your old bolt or use an old barrel and or possibly an old bolt this would seem to be more important. Don't get me wrong I know it is better to check it to be sure.

Hi what go no go gauge would you use for 223 wylde a .223 rem or 5.56 or 223 wylde ? thanks

good info

If the barrel is installed, why can't you just hit the bolt release to chamber the head space gauges without disassembling the bolt? I mean all they are is just inert rounds what could happen?

its been a goal of mine to build my own for years now and i finally had the extra cash to do it. So i scowered the internet for the type of parts i wanted and like most people im on a budget so i looked for the best deals i could. I found a 16" Chrome lined 1:7 twist NATO 5.56 for $145 from DSA Arms Inc. And they had them readily in stock so i purchased one. Last weekend i built the entire rifle from the parts i had been collecting. The whole gun from scratch. I put it all together and it came out looking and feeling great. I was very happy with how it all went. Today after i work i came home n grabbed the upper off the rifle and headed tot the local gunsmith to have the headspace checked on it just to make sure it was good to go n didnt want any surprises touching off the first round. He took the rifle in back and a few minutes later came walking back "Headspace is no good"…MOTHER F*****R. He used ejectorless gauges and then took the ejector out just to make sure and sure as shit…didnt close on the field gauge. The barrel was brand new out of the box. How could it have bad headspace? Needless to say i was bummed out, but happy that i had it checked. Came home with my paperweight and called up the company and told them what the deal was. They called back about 10 minutes later and told me that they would be emailing a shipping label to have the barrel and the components it shipped with sent back to them for "fixing" or if needed complete replacement. I didnt think you could fix a barrel that had bad headspace because the gas port is already drilled. Has anyone else encountered this problem before? or did i just win the lottery in the AR15 barrel world?

Notice he didn't disassemble the bolt. Using this method should I still plan on disassembling the bolt, or not? Just want to confirm as I will see if my FFL has some gauges to check my bolt (bought) and barrel (not bought) when I get them.

So if I'm just replacing the upper, using the same BCG and barrel there should be any issues?