AR15.Com Archives
 Check Headspace or not? (First Build)
bergz222  [Member]
8/24/2010 4:36:09 PM
First of all I did a search, and read through all the sticky's and the library, but I still couldn't get a clear answer. Should I check the headspace on my rifle before the first fire? It is all brand new from barrel to buttstock. I plan on cycling blanks through first, then test firing some blanks before switching to live rounds the first time. I was thinking about taking it to the local gun store and having the smith's check it out before I fire it, but I don't know. Keep in mind this is my first build and I'd rather not have a bad experience, I would like to build more ar's in the future .
MSPRet  [Member]
8/24/2010 4:40:49 PM
With all new components, barrel and bolt especially, you should be GTG. Don't waste time with blanks buddy, go out and pull the trigger...have fun and congratulations on your first completed build....<><....:)
bergz222  [Member]
8/24/2010 4:46:53 PM
It's not 100% complete yet.....I have all the parts, just need to get to a vice, the drill press and mig welder.....you guys know what I'm gonna do tomorrow haha. Luckily for me I work at a maintenance shop and have all that available. I guess I'm just nervous about the first fire.
cordovamx  [Member]
8/24/2010 4:52:59 PM
Originally Posted By bergz222:
It's not 100% complete yet.....I have all the parts, just need to get to a vice, the drill press and mig welder.....you guys know what I'm gonna do tomorrow haha. Luckily for me I work at a maintenance shop and have all that available. I guess I'm just nervous about the first fire.


just fire away, you'll be fine. What do you need a mig welder for?
bergz222  [Member]
8/24/2010 4:55:07 PM
bought a 14.5 inch barrel, need to permanently mount the flash hider.
Ghoulardi  [Member]
8/24/2010 5:24:57 PM
always a good idea to check headspace, 99 times out of a 100 it will be good, but there is always that 1. you don't need to buy gauges, unless you just want them. take the rifle to a good gunsmith that is local, and he can check it for you. any competent gunsmith will have 5.56 gauges. it shouldn't cost that much to have it check, I know it will be far less then reconstructive surgery.
altopwescap  [Member]
8/24/2010 7:24:22 PM
Given your situation and lack of experience with the platform, have the headspace checked and have a gunsmith double check your handy work before you fire a round.
GHPorter  [Team Member]
8/24/2010 8:14:11 PM
Originally Posted By Ghoulardi:
always a good idea to check headspace, 99 times out of a 100 it will be good, but there is always that 1. you don't need to buy gauges, unless you just want them. take the rifle to a good gunsmith that is local, and he can check it for you. any competent gunsmith will have 5.56 gauges. it shouldn't cost that much to have it check, I know it will be far less then reconstructive surgery.


Way more than 99 times out of 100 on that. But will your local "smith" really know how to do the check? The ONLY time I had an AR's headspace checked (all new, but my father in law wanted me to "be sure") I asked the (really a good) smith at a very well known shop to check it out. He humored me and did the check, right in front of me. You really need to know and trust whomever you ask to do this test-they may not really know how to do it and could tell you incorrectly that it's either good or not good.

With a BRAND NEW barrel and BRAND NEW bolt from (here's the important part) REPUTABLE SOURCES, the headspace WILL BE good. That means that if you get the barrel from some reliable source (let's say BCM) and the bolt from another (how about PK FIrearms) then it is 100% certain that these new parts will produce safe headspece because new parts MUST-it's part of the basic specs for these parts.

To the OP, if you have a firm like ADCO permanently attach your muzzle device, they may also be able to double check the headspace for you. You'd just have to provide your bolt.
Russ4777  [Team Member]
8/24/2010 8:23:09 PM
Be safe. Have your local gunsmith check the headspace to be sure.
HS2  [Member]
8/24/2010 8:28:11 PM
Originally Posted By bergz222:
bought a 14.5 inch barrel, need to permanently mount the flash hider.


Wow... mig welding, I really admire your ambition

Post some pics when you get it built. I agree with the previous comments. No need for blanks, get out and shoot it.
TCBA_Joe  [Team Member]
8/24/2010 8:53:32 PM
I've started checking headspace since getting brand new factory uppers at work that had headspace issues. between 15 and 20% of all bushmasters uppers didn't pass. We've stopped using them.
GHPorter  [Team Member]
8/24/2010 9:50:37 PM
Originally Posted By TCBA_Joe:
I've started checking headspace since getting brand new factory uppers at work that had headspace issues. between 15 and 20% of all bushmasters uppers didn't pass. We've stopped using them.


Well that throws "conventional wisdom" out the window, doesn't it? Were you able to swap bolts around to get decent headspace?
TCBA_Joe  [Team Member]
8/24/2010 10:14:49 PM
Originally Posted By GHPorter:
Originally Posted By TCBA_Joe:
I've started checking headspace since getting brand new factory uppers at work that had headspace issues. between 15 and 20% of all bushmasters uppers didn't pass. We've stopped using them.


Well that throws "conventional wisdom" out the window, doesn't it? Were you able to swap bolts around to get decent headspace?


Yeah. We have tons of spare parts so we always got a bolt/bbl combo tat worked, but should we really have to do that? I'd have to ask our armorer if they gauged "no-go" or "field", but buying a new rifle it better headspace "go" every time. I'm sure they would have been fine for casual plinking, but we run the guns HARD, and the uppers always seemed to fail prematurely. We've since swapped to LMT and are not having the issues we've experienced in the past and get almost double the round count per upper.
Gatorhunt  [Team Member]
8/25/2010 11:39:39 AM
Since I had problems with a build of mine (all quality parts from reputable companies) that turned out to be really tight headspace I have been checking headspace on all my rifles (builds and factory assembled) prior to firing. The gauges are only about 40 dollars for the whole set and they can save you some serious headaches at the range (which I can't afford to have since I'm limited to how often I can go) .... or possibly even save you from injury due to a KB.
odfox  [Team Member]
8/25/2010 12:42:50 PM
If the bolt and barrel were sold together (as a matched set or as part of a complete upper), I don't check. If I bought them either from different manufacturers or as separate purchases from the same manufacturer, I check.

The above post regarding bushmaster concerns me greatly.
bergz222  [Member]
8/25/2010 9:42:21 PM
Thanks for all the great replies guys, I really appreciate it, I'll get some pics up soon. Does anyone know of a good paint I can use to touch up the gun?
baxsom  [Member]
8/25/2010 10:16:27 PM
just get a field gauge and check, they are cheap and you will know for sure/.