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Posted: 11/27/2012 5:53:14 AM EDT
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I put together a DPMS AR in .308 and I can't get the bolt to close on the go gauge. I did remove the ejector. Any advice? Does this need to go back to DPMS? |
| SAAMI specs for .308 headspace are 1.630 - 1.640. So it's entierly possible they chambered to a near minimum spec and your gage is closer to the max. Both are correct just to a differnt tolerance. As long as it chambers rounds fine without forcing and there's no pressure signs on the brass I wouldn't sweat it. But if you're worried give them a call, ask what dimention they chamber to, then call clymer and find out the dimention on thier go gage. |
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There is a tolerance range on headspace gages.
Even the same manufacturer can only hold his tolerances within a range. SAI holds tight headspace and even they are normally a couple of thousandths longer than my Go gage. Fulton Armory has a decent FAQ on 308 headspace issues. You might want to read it before firing a round because it chambers. |
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On the SAAMI site 223 REM has been changed to match 5.56mm NATO headspace specs.
A match headspace gage set will check 308 WIN or 7.62mm chambers, but the specs for Go, Nogo, and Field are very different between the two. The 7.62 NATO case is typically stronger than the 308 WIN case. Safe 7.62mm headspace can far exceed the 308 WIN field limit. |
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