Checking headspace on a rem 700 .308.

[XxWoodsHunterxX]

New to reloading .308. Got Remington 700 stainless bolt action. Kinda nervous as to a few things I've heard from people about making sure to load rounds according to my rifles head-spacing???

Not sure what that means I load 45-70 and 556 but this is the first bolt action I've ever loaded for. I'm using. LC brass that was factory loaded and only fired from this rifle, Hornady 150gr SP, CCI primers. Any help

[ar15barrels]

Get one of these:

http://www.midwayusa.com/product/574297/rcbs-precision-mic-308-winchester

With that, you can measure the shoulder length of your fired cases.
Then, when you are setting up your sizing die, you will ensure that you are only pushing the shoulder back about 0.001" to 0.002".
That will ensure maximum reliability with long case life.

[2shotjoe]

Get one of these:

http://www.midwayusa.com/product/574297/rcbs-precision-mic-308-winchester

With that, you can measure the shoulder length of your fired cases.
Then, when you are setting up your sizing die, you will ensure that you are only pushing the shoulder back about 0.001" to 0.002".
That will ensure maximum reliability with long case life.

stop that, you're making me spend more.

[ar15barrels]

stop that, you're making me spend more.

Heaven forbid you have accurate tools to allow you to load more precise ammo...

Seriously though, it's hard to measure without good tools.
I suppose you could remove the striker and the ejector from your bolt and try to FEEL when the cases are JUST sized enough, but that's not as reliable as actual real quantified and repeatable measurements.

[Ubermcoupe]

stop that, you're making me spend more.

Now that you've saved me from buying it BH, I'm gunna hafta borrow that now

[kendog4570]

You can do it with a stripped bolt if you pay attention. Just remember, with a full length sizing die the shoulder datum dimension gets longer just before it gets shorter. The shoulder is the last portion of the case that gets sized, and prior to that the shoulder is the only place the brass can go during the sizing operation.

[killshot44]

I've used the RCBS Precision Mic and find that using the Hornady Case Comparator (with a Comparator body to attach to calipers) to measure set-back MUCH simpler.
Simply insert a fired case and measure. Then size the case until the measurement reads .002 (or desired set-back) less than the fired measurement.

Doing it by bolt drop with the firing pin removed as KenDog suggests also works if you're tool-adverse..

[russ69]

Get a case length gauge and you can find out what your fired cases measure, then adjust to put them right where you want them. It can also check your neck length and everything else, very handy.

http://www.lewilson.com/casegage.html

[waxer]

Get a case length gauge and you can find out what your fired cases measure, then adjust to put them right where you want them. It can also check your neck length and everything else, very handy.
http://www.lewilson.com/casegage.html

I have one of these, but from Dillon that I use to check this and it works pretty good.

[ar15barrels]

Get a case length gauge and you can find out what your fired cases measure, then adjust to put them right where you want them. It can also check your neck length and everything else, very handy.

http://www.lewilson.com/casegage.html

What measuring tool do you use to get an actual quantified measurement with a case gauge?

Most people just use those gauges to see if their ammo is "in spec" for what the gauge wants their ammo to be.
This unfortunately can be quite different than what their gun should use for best brass life/reliability.
I have measured a bunch of case gauges and some will make ammo that is actually way out of spec.

[ar15barrels]

I have one of these, but from Dillon that I use to check this and it works pretty good.

How many thousandths of an inch are you bumping your case shoulders while sizing?

[Glockrocks]

Get one of these:

http://www.midwayusa.com/product/574297/rcbs-precision-mic-308-winchester

With that, you can measure the shoulder length of your fired cases.
Then, when you are setting up your sizing die, you will ensure that you are only pushing the shoulder back about 0.001" to 0.002".
That will ensure maximum reliability with long case life.

I just got one of those, any videos on how to use it? First time reloading 308, reading instructions make me dizzy, I'm more of a visual learner

[ar15barrels]

I just got one of those, any videos on how to use it? First time reloading 308, reading instructions make me dizzy, I'm more of a visual learner

Three are 3 main measuring pieces plus the dummy bullet seating length tool.
The base has threads on the outside and a straight row of marks like a ruler.
The two different caps thread on to the base.
The cap with the largest through hole on top is for headspace.
The smaller hole one is for bullet seating length.
Take 3-5 fired cases and drop one at a time into the base with the primer side of the case into the base first.
Screw the headspace cap on with two fingers until it just touches the shoulder.
Touch it down 3-5 times and look what measurement you get each time it stops.
The measurement will generally be between -0.002" and +0.004"
Measure 3-5 cases and establish an average measurement for your gun.
Remember that dimension.

Now, go adjust your sizing die until you are moving the shoulder back 0.002" from your fired case dimension for your rifle.
Different rifles will have different dimensions.

[Glockrocks]

Thanks Randall, Your explanation makes more sense to me. Now I wish I didn't mix my bolt action and semi auto brass together I'll be sure to keep them separate on my next outing.

[ar15barrels]

Thanks Randall, Your explanation makes more sense to me. Now I wish I didn't mix my bolt action and semi auto brass together I'll be sure to keep them separate on my next outing.

Pick one kind of brass for your bolt gun and only use that kind.
Then, don't use that kind in your semi autos.
Then, you can always sort your cases again after co-mingling them in the tumbler...