View Full Version : Head spacing

04-16-2009, 2:30 AM
So I am building my upper and am wondering about head spacing. I have heard from several people that AR15 barrels are self head spacing. Then I was talking to my neighbor who is a war vet and he said I need to head space my upper. Who is right? By the way I have a Wilson fluted hbar. Any input would be great.

Major Pal
04-16-2009, 2:44 AM
for the most part AR stuff is perfect, but if ur worried just take it 2 a gunsmith, they r everwhere. PM me if ur in the bay area n i will help u

04-16-2009, 5:10 AM
I know this is A stupid qusestion but define headspacing ? , to me I thought it was A clearance issue with the upper .......Im A New to Smithing How much do most shops charge for head space?

04-16-2009, 8:59 AM

04-16-2009, 10:03 AM
For the most part you will be OK with your AR as long as you have NEW parts of good quality going in to the build. I have a field guage that I used to check a couple of the uppers I have assembled over the years, the field guage is long on headspace and if the bolt closes completely then there is a problem and the upper should not be fired. This is cheap insurance to be sure you are OK, you could get a complete set of go, no go, and a field guage but really the field guage will tell you what you need to know. BTW, headspace is a measurement from the breech face with the bolt closed to a static point on the shoulder area of the chamber in an AR, if the headspace is too long then the chamber is cut too deep or there is something out of spec in the bolt face.

04-16-2009, 12:19 PM
ARs that are in spec are headspaced. There are only 2 ways for them to be out of spec, 1) made incorrectly at the factory or 2) thousands of rounds of usage. If a company hasn't sent out a recall or warned you that a certain batch of their parts were out of spec and are dangerous to use, I'd say it would be a darn miracle if your AR is not headspaced correctly.

You say you are building it? I assume you are using new parts? If so you have nothing to worry about. If they aren't new, how used are they? Even if there are used it is still a rare chance your parts are out of spec.

IMHO, don't worry about it.

04-16-2009, 12:28 PM
Just like everyone else said above. Not much to worry about as long as all the parts are new and high quality. Headspacing is cheap insurance. YMMV

04-16-2009, 12:28 PM
Presuming all related components manufactured are within the specification, it should headspace correctly. That's the way it was designed.

If the parts are coming from reputable manufacturers, should be OK.

04-16-2009, 1:15 PM
If you're really worried, you can get a GI type headspace gauge that's go/no go.

04-16-2009, 2:15 PM
If you're really worried, you can get a GI type headspace gauge that's go/no go.

Here's where to get them: http://www.brownells.com/aspx/NS/store/ProductDetail.aspx?p=19183&title=.17%20-%20.22%20CALIBER%20RIFLE%20HEADSPACE%20GAUGES

04-16-2009, 4:05 PM
Thank you for all the info. All of the components I am using are new:

Mega upper
Young mfg chrome bolt
Gas busters charging handle
Wilson fluted hbar
Larue ff handguard
Larue gas block
Carbine gas tube
Miculek flash suppressor