new .308 brass headspace

BeerAlchemist

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Jul 12, 2009
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I just bought new .308 brass from Winchester for the first time since my spent casing collection ran out. I measured headspace and found many casings at 1.622. This seems excessively under headspaced to me given minimum case headspace is 1.627. My fire formed cases indicate my Rem 700 has a chamber headspace of 1.635, so this is a .013 difference in headspace. It seems like this is too much given the difference between a Go - Field gauge for that chambering is a range of .008 for safe tolerances. I'm assuming I'm missing something here?
 

Victor N TN

Retired civilian fart
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Feb 16, 2002
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Re: new .308 brass headspace

It's fine. Stop and think. The factory has to make brass that will fit EVERY size 308 chamber. It will be fine with normal loads.
 

Leaddog

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Oct 15, 2009
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Re: new .308 brass headspace

Shoot them and then resize. You'll see they come into your comfort zone quickly.
 

j-huskey

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Jul 27, 2001
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Re: new .308 brass headspace

I ran into something very similar with this one time. It was factory ammunition and I was going to a match at RO, and while practicing, I noted there was a 3' vertical string at 1000 yards.
Several days later, I determined the problem was the varied headspace which was similar to OP-BA above. I bought a different brand of ammunition and went to RO.

I still have the other lot of bad ammunition and still shoot it. I am getting good results, but the method SUCKS. I have to measure the headspace of every loaded round and sort them. Once sorted and fired in the sorted groups, they shoot fine at 1000 yards.

This can be a pain in the ass with a LARGE number of pieces of brass, in my case 2500 rounds, rather than a couple hundred.

Good luck.
 

BeerAlchemist

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Jul 12, 2009
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WA
Re: new .308 brass headspace

Thanks guys, I had an over pressure round that I thought was headspace so really looked into the details on that only to discover my loading was good, my observation skills sucked...a piece of military brass got into my collection and proved that you really do need to drop their loads by 1-2 gr over commercial. Anyway, it unnerved me a touch and got me extra cautious on my reloading.