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9/14/2014 3:18:34 AM EDT
I am going to build my own upper and I see some bolt manufacturers say that the headspace must be checked and adjusted by a gunsmith. What's up with that?
9/14/2014 7:14:22 AM EDT
[#1]
You have 3 options: Have a 'smith check it for you, find someone close by who can check it for you, or invest in the gages and check it yourself. But no matter which option you choose, get it checked BEFORE use, not after.
9/14/2014 9:23:00 AM EDT
[#2]
Quoted:
I am going to build my own upper and I see some bolt manufacturers say that the headspace must be checked and adjusted by a gunsmith. What's up with that?
View Quote

Who are the bolt mfg's ? Never seen that caveat on a site selling bolts before.
9/14/2014 1:16:44 PM EDT
[#3]
Checking HS is easy, adjusting it is EXTREMELY difficulty on an AR and usually not done.
9/14/2014 1:52:57 PM EDT
[#4]
Very rarely is a problem on any AR build if you go with quality components.

Vince
9/14/2014 11:06:33 PM EDT
[#5]
Just get a barrel with the extension already installed on it. With that there is no need to check headspace as long as you are using new good quality parts.

You might only want to do this if you were using an old bolt with a new barrel or vice versa.
9/15/2014 8:34:44 AM EDT
[#6]
Bolts have tolerances and a person can see up to a couple of thousandths variation in headspace by using different bolts.
Each to his own, but I always check headspace as I have seen new barrels fail headspace checks.
9/15/2014 11:26:20 AM EDT
[#7]
I advise to at the least check headspace....with a FIELD REJECT GAUGE.......I for one have built many parts guns and have not........but with that being said...........its advised to do so...........kinda like a lot of things in this world..........you assume the risk.................
9/15/2014 5:36:43 PM EDT
[#8]
Quote History
Quoted:
Just get a barrel with the extension already installed on it. With that there is no need to check headspace as long as you are using new good quality parts.

You might only want to do this if you were using an old bolt with a new barrel or vice versa.
View Quote

...Or if you're using a bolt from an unknown manufacturer and a barrel from a new-to-the-market manufacturer.  Then you could easily run into an issue of tolerances - or just plain "the barrel wasn't chambered right" - that make the combination of that bolt and that barrel unsafe.

When there were only three bolt manufacturers out there, and only a few companies made AR barrels, your advice would be great.  Now there are too many variables to just ignore the fact that someone is eventually going to wind up with a bolt that's a little short with a chamber that's a little long and wind up with way too much headspace.
9/15/2014 6:06:01 PM EDT
[#9]
Quote History
Quoted:

...Or if you're using a bolt from an unknown manufacturer and a barrel from a new-to-the-market manufacturer.  Then you could easily run into an issue of tolerances - or just plain "the barrel wasn't chambered right" - that make the combination of that bolt and that barrel unsafe.

When there were only three bolt manufacturers out there, and only a few companies made AR barrels, your advice would be great.  Now there are too many variables to just ignore the fact that someone is eventually going to wind up with a bolt that's a little short with a chamber that's a little long and wind up with way too much headspace.
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Quote History
Quoted:
Quoted:
Just get a barrel with the extension already installed on it. With that there is no need to check headspace as long as you are using new good quality parts.

You might only want to do this if you were using an old bolt with a new barrel or vice versa.

...Or if you're using a bolt from an unknown manufacturer and a barrel from a new-to-the-market manufacturer.  Then you could easily run into an issue of tolerances - or just plain "the barrel wasn't chambered right" - that make the combination of that bolt and that barrel unsafe.

When there were only three bolt manufacturers out there, and only a few companies made AR barrels, your advice would be great.  Now there are too many variables to just ignore the fact that someone is eventually going to wind up with a bolt that's a little short with a chamber that's a little long and wind up with way too much headspace.


Good point.
I guess my advice comes from only buying BCM,Rainier, ect/ quality companies. Why risk it? I guess if you are trying to save a few $ than by all means try one of those "Variables" but definitely check the headspace.
9/16/2014 6:50:06 AM EDT
[#10]
Companies like BCM and Rainier do not manufacture their own bolts and barrels.  They have them made (theoretically) to their specs.  What happens when contractor A makes a few off bolts?  Well when BCM hears about it, they send you a new bolt and they're fine.  That doesn't really address the issue YOU have though; if you don't check the headspace before you fire that rifle, you just might be contacting BCM from the hospital.  Extreme case, yes, but the point is that it is NOT about "reputable" vendors, it's about tolerances, and checking headspace means you're assessing whether or not those parts' tolerances are going to stack for you or against you.
9/16/2014 9:39:31 AM EDT
[#11]
Quote History
Quoted:
Companies like BCM and Rainier do not manufacture their own bolts and barrels.  They have them made (theoretically) to their specs.  What happens when contractor A makes a few off bolts?  Well when BCM hears about it, they send you a new bolt and they're fine.  That doesn't really address the issue YOU have though; if you don't check the headspace before you fire that rifle, you just might be contacting BCM from the hospital.  Extreme case, yes, but the point is that it is NOT about "reputable" vendors, it's about tolerances, and checking headspace means you're assessing whether or not those parts' tolerances are going to stack for you or against you.
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OK gocha.
9/18/2014 8:35:49 AM EDT
[#12]
Quote History
Quoted:
I advise to at the least check headspace....with a FIELD REJECT GAUGE.......I for one have built many parts guns and have not........but with that being said...........its advised to do so...........kinda like a lot of things in this world..........you assume the risk.................
View Quote

In my experience I have yet to see a new weapon fail a No-go gage however I have seen several Go gage failures.
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