Question on resizing .308 brass to 7mm-08

Snakehunter

Snakehunter

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Hi,
A buddy just gave me a bag of mixed headstamp .308 brass to resize to my 7mm-08. After cleaning I ran it through my Lee decapping/resizing die.
I loaded 20 with 140gr. Nosler Ballistic Tip and 20 with Sierra 140gr. Spitzers.
Took the rifle, Savage Axis, and bullets to the range today and found the cartridges were an absolute bear to get loaded. They were picked up off the magazine okay and smooth into the chamber, just the last 1/8" of bolt would just stop dead and wedge solid.
I don't know what I have done wrong. This is my first attempt at resizing the .308's and according to my caliper measurements match up pretty well to spec.
Just wondering if I should screw down my die another turn or two and try again. Would like some input from more knowledgeable folks here before I screw up my brass.
Thanks for any help,
Glen
 
Yes, you may have to turn down your die to "bump up" harder so those cases are sized enough to go into the chamber of your 7-08.

You can take a case, and size it, then try to chamber it. If it is tight, screw your die down 1/16 of a turn and size it again, then try it again.

Keep going in 1/16 turn increments until the formed 7-08 case just enters the chamber easily. secure the lock ring on your sizing die, and you are done.

Do not tighten the die anymore than is necessary to get the case to enter the chamber, or you will invite case separations later.

Regards, Dave.
 
This is not uncommon, I have had that problem with both two, 243 rifles and a 7-08. In all cases I was just resizing proper brass for the rifles, but was using old, quite often shot, brass.
The old brass we resize has hardened with use. When we full length resize it the shoulder pushes back, just like it should, but when the case comes out of the die the shoulder springs forward a bit, just enough to keep the case from fitting properly in the chamber.
The solution is to anneal the cases before you attempt to resize them down to 7mm.
This comes about from rifles with very minimum head space, which is common with newer rifles. With proper annealing of the shoulder area they should slide right into the chamber and the bolt close effortlessly, after full length resizing.
Just make sure your sizing die is turned down tight enough on the shell holder that it pushes the case fully in, under the pressure of sizing.
 
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i also had the same issue... i routed the problem to be that compressing the .308 down to 7mm makes the neck thickness just a thicker. Not 1 would even get close to chambering in my buddys Rem 770. Jump back to 7mm-08 brass and no issues... I believe that once u seat the bullet it pushes the neck back out just that tinniest amount. and when u go to chamber the round the neck simply is just to fat. Possibly the same issue??? try loading one.. where it stopes measure your bolt.... then simply close your bold and measure the difference.. if its length of the neck then u know where the issues beings

Cheers
Josh
 
I resized fifty mixed 308 cases to 7mm-08 using the Lee Pacesetter die set. Cases were then trimmed to length using the Lee Trim Gage and cutter. I had no problems chambering in a Savage Axis...
 
UPDATE - I had a go at bumping the shoulder back and still the cases were tight in the action. Did some more research and found some interesting articles on lubricating cases.
I was using a spray lube as it is has proven really easy in the past. I took a bunch of problem sized brass and lubed them with Lee Case Sizing Lube and with one super easy pass I had the cases resized and working properly. Turned out the spray lube was okay for full length resizing in own caliber but wouldn't allow the case to properly engage the neck and shoulder area in resizing to a different caliber. I think this would have been nigh impossible had I wanted to go down to a .260 for example. The articles I read recommended Imperial Wax but there was quite a lot of write-ups suggesting the Lee stuff instead. I had Lee lube on hand. It worked great.
Thanks for the help here once again my friends,
Glen
 
Just to go back a bit here. When you resize brass it should be tried in the rifle chamber before you reload it. Taking measurements with a caliper is not precise enough.
Use your rifle chamber for measurement, unloaded brass.
Enjoy
 
Agreed. This is the first time I have tried resizing. Relying on measurements didn't work for me as you suggest.
Lesson learned.
b72471 said:
Just to go back a bit here. When you resize brass it should be tried in the rifle chamber before you reload it. Taking measurements with a caliper is not precise enough.
Use your rifle chamber for measurement, unloaded brass.
Enjoy
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