Guidance Needed

[Hsargent21]

Ok got a question. Been reloading for 23 years and never had a head separation issue. I’m loading a mild load in a 308. Getting a few pieces of brass with a crack about .345 from case base after firing 3 times.

Load is 42 grains of Varget
Lake City Brass FL sized to 3.620
178 gr ELD-X
2575 FPS
Win LR Primer

Rifle
Rem 700 308
REMAGE Criterion Barrel

I think I have a headspace issue.

Once Fired Brass FL resized to 3.620
Then fired in this rifle length 3.636
I headspace the barrel with a Forster Headspace Go Gauge which measures 3.635.

After firing in this rifle I bump the shoulder back to 3.634.

I have checked headspace several times with the gauge and it is on.

What am I missing?

Did I resize the brass too much to start?

Should I set the barrel back so my brass stays closer to 3.620?

Also thinking I should chunk the brass and start over with Lapua.

Ok...fire away.

 

[Doug Beach]

No dimension on a .308 case measures 3.xxx inches. What are you measuring, exactly?

 

[Doug Beach]

If the first digit of your measurements was a 1, then your once fired brass at 1.620” had .016” excess headspace, which is excessive. Case failure is not surprising.

 

[Richard Coody]

Obviously you are.oversizing your brass. One times fired isn't even fully fireformed and you shoulder bumped 16 thousands.

Start over and find someone who can mentor you.

 

[Hsargent21]

Yep...sorry for the measurements...that is with the Hornady comparator

 

[Hsargent21]

Also...I bought once fires brass. So I started with a full length resize.

 

[Doug Beach]

If your once fired brass measures 1.620 as purchased, it needs to be scrapped. Do not use it.

 

[Hsargent21]

It does measure 1.620. Copy all. Going in the trash. What should it be?

 

[Doug Beach]

It does measure 1.620. Copy all. Going in the trash. What should it be?

Not less than 1.627”, per SAAMI.
Once you have fired it, there’s no reason to set it back more than .002” from fired dimensions, in a bolt action, .003” in a gas gun.

 

[Hsargent21]

Thx Doug...lesson learned...glad it was Lake City brass and not Lapua...would have taken a 12 pack to get over it...

 

[J F Johannes]

I would consider getting the match gauges to set headspace on that rifle with the Remage barrel. I believe you are using the NATO set by Forster. The match set is a 1.630 GO and a 1.633 NO GO I believe. That's what I use at least. New Lapua cases are going to come in at about 1.622 +/-. Do a search here on fire forming new brass and setting headspace. I would explain further but why, it's all here on the forum already. I am nauseated now and all I need is for F Guffey to ring in with his BS on headspace. Be safe!

Jim

 

[Metal God]

Wait a second guys , first the Hornady ( Headspace gauge ) "comparator" is not a absolute measuring tool . Mine measures my go gauge .009 short which is no big deal because the tool is not designed to measure anything . It is designed to compare one case to another and it does that quite well .

The question is what should you do ? Take a fired case from your rifle and "measure" it with your comparator . While the fired case is still in the comparator zero your calipers . You now want to size your cases -.002 to -.003 using your zeroed to your fireformed case comparator . Or just size them .002 or .003 less then the actual measurement you got . So if your fired case measures 1.629 with your comparator . Your sized cases should measure 1.627 to 1.626 .

 

[carlsbad]

You don't have a headspace problem, you don't have your die set up correctly. screw your sizing die out until the sized case is .002" shorter than the fired round as measured with a shoulder attachment on your caliper. --Jerry

 

[Hsargent21]

Ok...so here is where I’m at. My headspace gauge is 1.630. My fired cases are 1.632. Where I goofed is when I FL resized the cases when I received them. They measure 1.615 after I resized them. Are they garbage? I pulled 20 cases to work my load with. At my 4th firing of these 20 cases I found several with the crack.

 

[Hsargent21]

After I resized them the first time I did adjust the die to only bump them back to 1.628.

 

[J F Johannes]

Ok...so here is where I’m at. My headspace gauge is 1.630. My fired cases are 1.632. Where I goofed is when I FL resized the cases when I received them. They measure 1.615 after I resized them. Are they garbage? I pulled 20 cases to work my load with. At my 4th firing of these 20 cases I found several with the crack.

So now your gauge 1.630 and not 1.635. So what about the NO GO? Do you have one?

Jim

 

[Hsargent21]

Jim...I’m learning through this thread. I used the go gauge to calibrate my dial calipers. I don’t have a no go guage.

 

[carlsbad]

I'm gonna make you $20.

Sell the go gauge. it is irrelevant.

Your calipers don't need to be calibrated.

All that matters is the fired brass and the sized brass.

They should be .002" apart.

--Jerry

 

[Metal God]

I agree with Carlsbad , Your gauge is irrelevant in this situation . All's that matters is your chamber size and your sized case size and how they compare .

 

[Texas10]

At this point it looks like you've got things straightened out, so a couple of things come to mind that might nevertheless help, issues that have come up personally when installing a barrel, and hand loading for the first time.

First of all, headspace gages can be made or labeled incorrectly. And lacking tools to make absolute dimensional measurements, and without removing the barrel to check the gage accuracy, how to know you're in the ball park on headspace, particularly after seeing signs of case wall separation?

I just installed a Shilen Select Match barrel in 308. My first rounds down the barrel were FGGM 168 gr factory ammo. I measured the case base to shoulder on the new rounds, and again after shooting. Then I re-chambered the shot brass to check fit with this brass that has a reputation of being soft and growing to fit the chamber. All chambered fine, so I put two layers of scotch tape on the head of one spent case and chambered it again. Bolt would close, but very stiff, so I knew my brass was close to fully fireformed.

I measure and then FL size the cases with the die set long so I don't bump the shoulder. Fire again and check fit to chamber again after this, the second firing. Bolt will close stiff on some, not close on others. I select one case that the bolt drop is only slightly stiff and keep and label this as my chamber length gage. All future measurements are compared to this gage, unless I pull the barrel for some reason, then it's time to start over.

Secondly, I'd recommend you retire the dial calipers and buy digital. You can zero the display with the Hornaday gage installed and eliminate all the mental gymnastics, particularly useful when you need to use two gages on the caliper to measure cases with the spent primer still installed, ie. an OAL gage on one blade to avoid the primer bulge, and headspace comparator on the other.

Happy shooting!