Jump to content
308AR.com Community
  • Visit Aero Precision
  • Visit Brownells
  • Visit EuroOptic
  • Visit Site
  • Visit Beachin Tactical
  • Visit Rainier Arms
  • Visit Ballistic Advantage
  • Visit Palmetto State Armory
  • Visit Cabelas
  • Visit Sportsmans Guide

Bolt specs?


Recommended Posts


I just got my new BA 16" barrel  government profile today, and I went to check headspace, with the bolt extractor and ejector removed. I tried the go gauge and the bolt would turn and lock up, a bit sloppy though. Then on the No-go gauge it will at first not close but with a bit of wobbling the bolt it will then lock in tightly and slightly rotate as well. 
I am wondering if anyone has the dimensions of the LR-308, DPMS profile bolt. I am thinking that this bolt is out of spec or the wrong profile, not DPMS. 

Here are some pics of the headspace gauges that I purchased and also of the bolt. I marked A. for bolt face depth, B. for locking lug width, C. for locking lug length. Would like all the dimensions of a DPMS profile bolt please if anyone has them. Thank you. 

I am still thinking this BCGs bolt is out of spec, or isn't the correct profile for this barrel, 16" .308 TACTICAL GOVERNMENT MIDLENGTH AR 308 BARREL, MODERN SERIES. 



Edited by Lr-308FUn
Link to comment
Share on other sites

39 minutes ago, Lr-308FUn said:

I am thinking that this bolt is out of spec or the wrong profile, not DPMS. 

Doesn't have to be out of spec to see what you have. Just a barrel on one side of the tolerance and a bolt on the other. I have run into similar, field gauge showed it serviceable but that's supposed to be fore heavily used weapons. I have a few different spare bolts so have been able to swap bolts around to get a nice tight fit when I see the problem, twice out of maybe a dozen rifles. 

Link to comment
Share on other sites

Okay, I am new to this 308 AR builds, I did one about 2 years ago and didn't have any of these issues. I will check it with the other BCG I am getting tomorrow and see if its the same or perhaps right on. I am thinking with what you provided that this BCG might be AR10 spec instead of 308 AR. It is a tight fit to get it to lock up on the no go gauge, I do have the extractor and ejector removed. I had to take the barrel back off cause I forgot to headspace before barrel before assembly. 

Edited by Lr-308FUn
Link to comment
Share on other sites

Join the conversation

You can post now and register later. If you have an account, sign in now to post with your account.

Reply to this topic...

×   Pasted as rich text.   Paste as plain text instead

  Only 75 emoji are allowed.

×   Your link has been automatically embedded.   Display as a link instead

×   Your previous content has been restored.   Clear editor

×   You cannot paste images directly. Upload or insert images from URL.

  • Create New...