Is it necessary to head space the barrel and bolt. I have received conflicting information regarding this topic. Some say don't bother since everything is made to the same spec and others say head spacing is absolute must.
AR15 Head spacing barrel and bolt
- Thread starter Rock Head
- Start date
Re: AR15 Head spacing barrel and bolt
Some people say if you buy quality components then it is not necessary. I've also read other people's opinions that you can't alter headspace on AR's (really, so why do people advise that you try multiple bolts if you have headspace issues???).
But you sure as sh!t can buy out of spec components, combine mismatched components or make mistakes during assembly.
For the cost of a set of go/no-go gauges ($20/30?) I'd ask why would you <span style="font-weight: bold">not</span> check headspace?
Or if you're not up for spending on them yourself, get a qualified armourer/gunsmith to check your build for you before firing.
Don't take chances with safety....EVER!
But...it's your face/hands/eyes
Me? I'm used to mine the way they are...so will always check and double check everything (headspace, torque, function etc.) before putting a live round in the chamber.
Some people say if you buy quality components then it is not necessary. I've also read other people's opinions that you can't alter headspace on AR's (really, so why do people advise that you try multiple bolts if you have headspace issues???).
But you sure as sh!t can buy out of spec components, combine mismatched components or make mistakes during assembly.
For the cost of a set of go/no-go gauges ($20/30?) I'd ask why would you <span style="font-weight: bold">not</span> check headspace?
Or if you're not up for spending on them yourself, get a qualified armourer/gunsmith to check your build for you before firing.
Don't take chances with safety....EVER!
But...it's your face/hands/eyes
Me? I'm used to mine the way they are...so will always check and double check everything (headspace, torque, function etc.) before putting a live round in the chamber.
Re: AR15 Head spacing barrel and bolt
If you are buying all the parts now you can often buy the barrel and bolt from the same vendor, and have them check headspace before shipping the parts.
If you are buying all the parts now you can often buy the barrel and bolt from the same vendor, and have them check headspace before shipping the parts.
Re: AR15 Head spacing barrel and bolt
CNC - that's true. But I'd still double check with a gauge once the rifle is assembled for safety's sake.
CNC - that's true. But I'd still double check with a gauge once the rifle is assembled for safety's sake.
Re: AR15 Head spacing barrel and bolt
I agree Basra, just cuts down on the odds of getting a mismatch.
I agree Basra, just cuts down on the odds of getting a mismatch.
Re: AR15 Head spacing barrel and bolt
You'll get conflicting information here too. I don't check it, hopefully I never buy a bad part that made it thru QC. But I look at these type questions this way, you are concerned enough to ask if it needs to be checked, so do it or have it done, peace of mind and all that.
When it is said you canot alter headspace in an AR they mean that contrary to the somewhat popular belief tightening/loosening the barrel nut does not effect it. This being why if you purchase a headspaced bolt and barrel you cannot f-up and change the headspace, nothing you do during normal, by hand and torque wrench assembly, will change how the bolt lugs engage in the barrel extension.
You'll get conflicting information here too. I don't check it, hopefully I never buy a bad part that made it thru QC. But I look at these type questions this way, you are concerned enough to ask if it needs to be checked, so do it or have it done, peace of mind and all that.
When it is said you canot alter headspace in an AR they mean that contrary to the somewhat popular belief tightening/loosening the barrel nut does not effect it. This being why if you purchase a headspaced bolt and barrel you cannot f-up and change the headspace, nothing you do during normal, by hand and torque wrench assembly, will change how the bolt lugs engage in the barrel extension.
Re: AR15 Head spacing barrel and bolt
beef - my point exactly.
You can read opinions that support either option. Opinions = assholes in that everybody has one.
So what is the guy to do?
For the sake of the price of a set of gauges - if you aren't sure or can't make up your own mind...forget the different opinions and trying to work it out.
Check it and be safe.
After all - it is not the guys on the internet who say don't bother that are ever going to have to pick up the pieces (either of your ruined face/hand or worse) if you happen to be the guy who has the misfortune to be the exception to prove them wrong.
beef - my point exactly.
You can read opinions that support either option. Opinions = assholes in that everybody has one.
So what is the guy to do?
For the sake of the price of a set of gauges - if you aren't sure or can't make up your own mind...forget the different opinions and trying to work it out.
Check it and be safe.
After all - it is not the guys on the internet who say don't bother that are ever going to have to pick up the pieces (either of your ruined face/hand or worse) if you happen to be the guy who has the misfortune to be the exception to prove them wrong.
Re: AR15 Head spacing barrel and bolt
I take a dummy round (sized the way I want it), the barrel and bolt and chamber it by hand. Then, I cut a circle out of a playing card and place it on the bolt face and try again. If it is very very tight/impossible to do I figure it is fine, if it chambers easily I take it to a smith as it might be field spec might not. I have built many rifles this way and haven't had a problem.
I take a dummy round (sized the way I want it), the barrel and bolt and chamber it by hand. Then, I cut a circle out of a playing card and place it on the bolt face and try again. If it is very very tight/impossible to do I figure it is fine, if it chambers easily I take it to a smith as it might be field spec might not. I have built many rifles this way and haven't had a problem.
Re: AR15 Head spacing barrel and bolt
<div class="ubbcode-block"><div class="ubbcode-header">Originally Posted By: RockHead</div><div class="ubbcode-body">Since you put it that way, thats all I need to hear. For $20 I'll get a set of go no-go gauges. </div></div>
Gauges don't let you set/adjust headspace.
<div class="ubbcode-block"><div class="ubbcode-header">Originally Posted By: RockHead</div><div class="ubbcode-body">Since you put it that way, thats all I need to hear. For $20 I'll get a set of go no-go gauges. </div></div>
Gauges don't let you set/adjust headspace.
Re: AR15 Head spacing barrel and bolt
When I went to a major AR/M4 manufacturer's armorer training, we were told not to worry about it. Everything built to spec, etc, etc. 3 years later, time to recertify, that manufacturer wasn't holding a class near me, but another major manufacturer was, so I went to that class. This instructor taught that you absolutely needed to check, talked about component wear, tolerance stacking, etc. Then took one ot my rifles and checked it and it wouldn't close on a go gauge. I check all of our rifles at every inspection now. Also, just because the barrel is stamped 5.56, it may still be chambered/throated for 223. I have 3 rifles in our inventory like that, marked 5.56, throats are .223. It took me a while to determine why they were blowing primers on XM-193 ammo. It is always better to know for sure what you have, markings can be wrong, reams worn out, maker hung over, who knows. Check 'em, then YOU know.
When I went to a major AR/M4 manufacturer's armorer training, we were told not to worry about it. Everything built to spec, etc, etc. 3 years later, time to recertify, that manufacturer wasn't holding a class near me, but another major manufacturer was, so I went to that class. This instructor taught that you absolutely needed to check, talked about component wear, tolerance stacking, etc. Then took one ot my rifles and checked it and it wouldn't close on a go gauge. I check all of our rifles at every inspection now. Also, just because the barrel is stamped 5.56, it may still be chambered/throated for 223. I have 3 rifles in our inventory like that, marked 5.56, throats are .223. It took me a while to determine why they were blowing primers on XM-193 ammo. It is always better to know for sure what you have, markings can be wrong, reams worn out, maker hung over, who knows. Check 'em, then YOU know.
Re: AR15 Head spacing barrel and bolt
What companies offer AR armorer training that isn't LE/Mil only? I'm no longer on active duty, but I am still DoD, and I can get on bases and whatnot.
What companies offer AR armorer training that isn't LE/Mil only? I'm no longer on active duty, but I am still DoD, and I can get on bases and whatnot.
Re: AR15 Head spacing barrel and bolt
I used to let this question wear my though process out. Basically, they are mil-spec and should be fine. 6 Builds and no problems.
I used to let this question wear my though process out. Basically, they are mil-spec and should be fine. 6 Builds and no problems.
Re: AR15 Head spacing barrel and bolt
<div class="ubbcode-block"><div class="ubbcode-header">Originally Posted By: Jim Buck</div><div class="ubbcode-body">Basically, they are mil-spec and <span style="color: #CC0000">should</span> be fine. 6 Builds and no problems. </div></div>
Bloke walks up to you in a pub. He says:
"I'll buy you a drink if you let me set off an explosion 6" in front of your face. Pressure will be around 62,000psi - but don't worry, it's in a steel contaner that I put together myself from parts I bought. It <span style="color: #CC0000">should</span> be safe - all the parts <span style="color: #CC0000">should</span> have been made to the correct spec/tolerances and <span style="color: #CC0000">should</span> have been put together right"
You ask:
"<span style="color: #CC0000">Should</span> be? Have <span style="text-decoration: underline">you</span> checked it yourself?"
He replies:
"No, I haven't actually <span style="text-decoration: underline">checked</span> it. But I've had no problems so far"
What do you do next?
(Jim Buck, no offense or disrespect intended but for me "<span style="color: #CC0000">should</span>" or "mil spec"doesn't constitute a guarantee that fit/safety can be taken for granted)
<div class="ubbcode-block"><div class="ubbcode-header">Originally Posted By: Jim Buck</div><div class="ubbcode-body">Basically, they are mil-spec and <span style="color: #CC0000">should</span> be fine. 6 Builds and no problems. </div></div>
Bloke walks up to you in a pub. He says:
"I'll buy you a drink if you let me set off an explosion 6" in front of your face. Pressure will be around 62,000psi - but don't worry, it's in a steel contaner that I put together myself from parts I bought. It <span style="color: #CC0000">should</span> be safe - all the parts <span style="color: #CC0000">should</span> have been made to the correct spec/tolerances and <span style="color: #CC0000">should</span> have been put together right"
You ask:
"<span style="color: #CC0000">Should</span> be? Have <span style="text-decoration: underline">you</span> checked it yourself?"
He replies:
"No, I haven't actually <span style="text-decoration: underline">checked</span> it. But I've had no problems so far"
What do you do next?
(Jim Buck, no offense or disrespect intended but for me "<span style="color: #CC0000">should</span>" or "mil spec"doesn't constitute a guarantee that fit/safety can be taken for granted)
Re: AR15 Head spacing barrel and bolt
I have persoanlly received a mismatched barrel and bolt combo from a very well known armory. I would very much suggest checking headspace if assembling your own rifle. The final responsibility always lies with the assembler.
FYI, you can change headspace by lapping your lugs. This is how I corrected the aforementioned situation. .001 to .002 is all I would attempt, though, due to the effort involved. (I hate lapping lugs).
I have persoanlly received a mismatched barrel and bolt combo from a very well known armory. I would very much suggest checking headspace if assembling your own rifle. The final responsibility always lies with the assembler.
FYI, you can change headspace by lapping your lugs. This is how I corrected the aforementioned situation. .001 to .002 is all I would attempt, though, due to the effort involved. (I hate lapping lugs).
Re: AR15 Head spacing barrel and bolt
I favor using head space gauges on ARs. Why? It's actually slightly over complicated for something you can build yourself.
First, you're going to get .223 gauges. You may have a 5.56 chamber depending on your barrel. So it's nice to know what you have and how it measures. Even if you're barrel is marked .223, it's most likely been cut with a Wylde reamer so the throat won't be the same. Since it spaces off the shoulder it shouldn't matter, but again why go blind when you can buy gauges cheaply?
Keep that in mind when comparing apples, .223 bolt gun, to oranges, .223 Wylde AR. Does that looser throat affect accuracy? I think that it does.
Second, jump over to a .308 platform. I NEVER hear of anyone buying a new head spaced bolt with their replacement barrel or they're not mentioning it. Let's complicate this by adding that you may be getting a 7.62 chamber vs. a .308.
I have a factory Armalite 16" 7.62 barrel that closes on a .308 no-go. I have a Douglas-Barnett barrel on an M14S that was cut with a M852 reamer. It closes on a .308 no-go. I have a replacement .308 AR barrel that was cut with a .308 Obermeyer reamer. It closes on a .308 no-go.
It's nice to know what you have when there's a controlled explosion going off a few inches away from your face/head, right?
I favor using head space gauges on ARs. Why? It's actually slightly over complicated for something you can build yourself.
First, you're going to get .223 gauges. You may have a 5.56 chamber depending on your barrel. So it's nice to know what you have and how it measures. Even if you're barrel is marked .223, it's most likely been cut with a Wylde reamer so the throat won't be the same. Since it spaces off the shoulder it shouldn't matter, but again why go blind when you can buy gauges cheaply?
Keep that in mind when comparing apples, .223 bolt gun, to oranges, .223 Wylde AR. Does that looser throat affect accuracy? I think that it does.
Second, jump over to a .308 platform. I NEVER hear of anyone buying a new head spaced bolt with their replacement barrel or they're not mentioning it. Let's complicate this by adding that you may be getting a 7.62 chamber vs. a .308.
I have a factory Armalite 16" 7.62 barrel that closes on a .308 no-go. I have a Douglas-Barnett barrel on an M14S that was cut with a M852 reamer. It closes on a .308 no-go. I have a replacement .308 AR barrel that was cut with a .308 Obermeyer reamer. It closes on a .308 no-go.
It's nice to know what you have when there's a controlled explosion going off a few inches away from your face/head, right?
Re: AR15 Head spacing barrel and bolt
<div class="ubbcode-block"><div class="ubbcode-header">Originally Posted By: sentry1</div><div class="ubbcode-body">What companies offer AR armorer training that isn't LE/Mil only? I'm no longer on active duty, but I am still DoD, and I can get on bases and whatnot. </div></div>
PM Sent with info on Armorer School.
<div class="ubbcode-block"><div class="ubbcode-header">Originally Posted By: sentry1</div><div class="ubbcode-body">What companies offer AR armorer training that isn't LE/Mil only? I'm no longer on active duty, but I am still DoD, and I can get on bases and whatnot. </div></div>
PM Sent with info on Armorer School.
Re: AR15 Head spacing barrel and bolt
<div class="ubbcode-block"><div class="ubbcode-header">Originally Posted By: RockHead</div><div class="ubbcode-body">Is it necessary to head space the barrel and bolt. I have received conflicting information regarding this topic. Some say don't bother since everything is made to the same spec and others say head spacing is absolute must.
</div></div>
Its quick and easy with a couple tools. And its not just for a new barrel and bolt combo. On High round count rifles as well.
<div class="ubbcode-block"><div class="ubbcode-header">Originally Posted By: RockHead</div><div class="ubbcode-body">Is it necessary to head space the barrel and bolt. I have received conflicting information regarding this topic. Some say don't bother since everything is made to the same spec and others say head spacing is absolute must.
</div></div>
Its quick and easy with a couple tools. And its not just for a new barrel and bolt combo. On High round count rifles as well.
