imschur Posted November 6, 2010 Report Share Posted November 6, 2010 Whether transitioning from building AR-15's or choosing a 308 AR for your first firearm build some safety considerations must be made.1. First off the bolt and the barrel need to be checked for proper headspace by someone qualified to do so. The fact that nobody is discussing disassembling the bolt carrier to remove the extractor and ejector concerns me. While the proper tools are available to verify headspacing yourself it can be tricky and confusing process if you haven't been trained to perform this task by someone qualified or experienced with the procedure.Do not put blind trust in the manufacturer of the barrel and bolt. 2. Do not use one bolt carrier group for multiple uppers. Each upper should have a dedicated bolt.3. Used Rifles - Because of the DIY nature of these rifles you cant assume the person you bought the rifle from did all the right things. Headspace should be verified bore firing the weapon4. When possible buy the barrel and bolt together by an organization that can verify the barrel and bolt headspacing so you dont have to worry about it.The face you save might be your own.Did I miss anything? Feel free to add and I will update the original post.lastly dont forget to have fun <thumbsup> Link to comment Share on other sites More sharing options...
TacBlade Posted November 6, 2010 Report Share Posted November 6, 2010 I better wear full body and head armor when I pull the trigger on mine for the first time tomorrow!! If you do not hear from me after tomorrow, well, you told me so!!! :( Link to comment Share on other sites More sharing options...
imschur Posted November 6, 2010 Author Report Share Posted November 6, 2010 Who's the guy dressed like an astronaut at the 200 yard range <laughs> Dont forget to run her wet <thumbsup> Link to comment Share on other sites More sharing options...
imschur Posted November 6, 2010 Author Report Share Posted November 6, 2010 BTW Brownells has this DVD from AGI. It's dry and boring, probably a VHS transfer but it does demonstrate headspacing pretty good. Link to comment Share on other sites More sharing options...
randybill Posted November 6, 2010 Report Share Posted November 6, 2010 this is exactly why i buy complete uppers for my projects! that, and i'm lazy. Link to comment Share on other sites More sharing options...
SWshooter Posted November 7, 2010 Report Share Posted November 7, 2010 From what I've seen on most barrel suppliers sites, they will supply a headspaced bolt for a reasonable price, or you can send them a bolt and they will headspace to it. That is one of the big pluses for the AR system, changing barrels is a snap, the headspace is built into the barrel-barrel extension assembly, and not dependent on barrel-receiver alignment. Link to comment Share on other sites More sharing options...
TacBlade Posted November 7, 2010 Report Share Posted November 7, 2010 Now I'm wondering if I should pull the trigger tomorrow after reading that statment above. I was assuming that ar15's and AR.308's were brassieres the same way. I've built several ar15's and never worried about headspacing and just fired them. They all were fine? Link to comment Share on other sites More sharing options...
imschur Posted November 7, 2010 Author Report Share Posted November 7, 2010 FWIW I believe that AR-15's should be verified as well. Im sure statistically the odds of a problem are small but men and machines can and do make mistakes.If you want to do it yourself a set of gages and a little knowledge will last a life time.Heres a bit of generic info and here's more.I'm sure there are many who disagree with me, so be it. I just want to be sure you guys are armed with the knowledge to prevent possible injury to yourselves and those around you."To measure is to know" Link to comment Share on other sites More sharing options...
survivalshop Posted November 8, 2010 Report Share Posted November 8, 2010 I have always checked head space ,even If I buy a used AR type rifle .Ya check to make sure the safety & fire control system works , why not head space ! Link to comment Share on other sites More sharing options...
awesymoto Posted January 4, 2011 Report Share Posted January 4, 2011 I have never really considered headspace an issue, until now... eek the only thing i've timed and head-spaced were M2's and 240's Link to comment Share on other sites More sharing options...
308reloaded Posted March 4, 2011 Report Share Posted March 4, 2011 now I feel stupid. I have never fired any rifle that I have built and have check head space on Friends builds. but not once have I ever checked the headspaceing on my pistol builds(1911) I just put them together and shoot them. dumb me now I will need to buy another set of gauges in 45acp. Link to comment Share on other sites More sharing options...
washguy Posted June 8, 2011 Report Share Posted June 8, 2011 Better Late Than Never...and im always a day late and a dollar short...lolSo, ive got my head space gauges coming...only after I popped some primers.....took the new beast out...functioned fine held bolt open every time after loading one.I then proceeded to shoot privi partizen 150grain soft point first box no probs no swipes brass looks good....shot some German Dag oh yeah it screams.....then went gack to a new box of privi 308....daaamn blown primers...then a bcg lockup...primer piece stuck found only after range officer beat the crap out of my charging handle rendering it uselesstrying to unlock it....got a gunfighter on the way and headpace gauge...but I really do think its the crap privi ammo btw the sass barrel is 762 :) Wash Link to comment Share on other sites More sharing options...
henmar77 Posted December 14, 2011 Report Share Posted December 14, 2011 I've seen plenty of videos and write up about headspacing, but no one ever talks about how to correct it! So you determine that your headspacing is wrong. Then what????? Please dont say take it to a gunsmith, the point of this is DIY. Link to comment Share on other sites More sharing options...
washguy Posted December 14, 2011 Report Share Posted December 14, 2011 I've seen plenty of videos and write up about headspacing, but no one ever talks about how to correct it! So you determine that your headspacing is wrong. Then what????? Please dont say take it to a gunsmith, the point of this is DIY.Hiya Hen you know thats a great question!I read where some folks who are getting a barrel...buy the bolt from the same mfg...so its headspaced for you. so they say?....so im thinkin the mfg is taking different bolts and fit them to to chamber...and by "fit" i mean grabbing a bolt out of a bunch of bolts and finding one that headspaces....I guess a true barrel maker would use a chamber ream/adjust barrel extension to achieve this but im thinkin all the others just "try fit"so diy ...hmmmm what would we do? ive built over 30 ar's for me and friends over the years and never had a headspace problemo....but I do check for headspacing . The 308 in the post above scaaared the crap out of me...wasnt the headspace.. it was crap ammo....didnt have a headspace gauge for a 308/762. I do now! <munch> Wash Link to comment Share on other sites More sharing options...
imschur Posted December 14, 2011 Author Report Share Posted December 14, 2011 Headspace is not adjustable by the end user. It is a safety check to prevent bodily harm to yourself and those around you. Link to comment Share on other sites More sharing options...
henmar77 Posted December 14, 2011 Report Share Posted December 14, 2011 Hiya Hen you know thats a great question!I read where some folks who are getting a barrel...buy the bolt from the same mfg...so its headspaced for you. so they say?....so im thinkin the mfg is taking different bolts and fit them to to chamber...and by "fit" i mean grabbing a bolt out of a bunch of bolts and finding one that headspaces....I guess a true barrel maker would use a chamber ream/adjust barrel extension to achieve this but im thinkin all the others just "try fit"so diy ...hmmmm what would we do? ive built over 30 ar's for me and friends over the years and never had a headspace problemo....but I do check for headspacing . The 308 in the post above scaaared the crap out of me...wasnt the headspace.. it was crap ammo....didnt have a headspace gauge for a 308/762. I do now! <munch> WashThanks for posting this. 30 builds with no headspacing problems is what i want to hear. This is very reassuring. At least it gives me some confidience that the MFG are doing something right. I can deal with the cost of the gauge, its the cost of what the gauge might find wrong that worries me. Link to comment Share on other sites More sharing options...
edgecrusher Posted December 14, 2011 Report Share Posted December 14, 2011 better than the cost of life and limb. it's a safety precaution, and like wash said, most of the time you will be good to go. it's just just better to be sure. Link to comment Share on other sites More sharing options...
imschur Posted December 14, 2011 Author Report Share Posted December 14, 2011 If you read the threads there are some with various topics regarding bolts closing issues. Remember these is no milspec and these arent AR-15's. Also a lot more energy to help Darwins cause. Link to comment Share on other sites More sharing options...
henmar77 Posted December 14, 2011 Report Share Posted December 14, 2011 Headspace is not adjustable by the end user. It is a safety check to prevent bodily harm to yourself and those around you.Why do they sell tools for this then for DIYers? Link to comment Share on other sites More sharing options...
imschur Posted December 14, 2011 Author Report Share Posted December 14, 2011 Because it's a safety check Link to comment Share on other sites More sharing options...
henmar77 Posted December 14, 2011 Report Share Posted December 14, 2011 Because it's a safety checkI mean to change headspacing, not to check for it. Reason for checking headspacing is a no brainer. Link to comment Share on other sites More sharing options...
98Z5V Posted December 14, 2011 Report Share Posted December 14, 2011 You can buy a chamber reamer, but that's not the DIY way to change headspace problems. It can help with minor problems with headspace, but that's a backwards way to go about things if there's a bigger problem.The only "DIY" way to set headspace - is to be a barrel builder. I've posted the steps involved before, so a search might turn up what all gets done, and the order they're done in. Link to comment Share on other sites More sharing options...
soofley Posted December 14, 2011 Report Share Posted December 14, 2011 ok reading this thread makes me not want to shoot my future .308 .... anyone knoe if rainierArm ultramath+dpms headspacing is ok? i guess i can bring it to rainier to get it inspected.what injury am i looking to get if my headspacing it no good? an eye and an arm? Link to comment Share on other sites More sharing options...
imschur Posted December 14, 2011 Author Report Share Posted December 14, 2011 If you buy a barrel and bolt from Rainier they will verify for you. They do the same for AR-15's. As mentioned earlier a set of gauges is a worthy investment. Also I feel ANY used rifle should be checked.BTW there are many who disagree with me on this. Link to comment Share on other sites More sharing options...
washguy Posted December 15, 2011 Report Share Posted December 15, 2011 If you buy a barrel and bolt from Rainier they will verify for you. They do the same for AR-15's. As mentioned earlier a set of gauges is a worthy investment. Also I feel ANY used rifle should be checked.BTW there are many who disagree with me on this.Heres THE reason you are so right!My Mom used to say "its all fun till somebody looses an eye! "nuff said! <thumbsup> Wash Link to comment Share on other sites More sharing options...
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