Resized brass tight? Problem solved

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skhunter

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I am loading for an 7MM STW. When I fire a shot the brass extracts easily. The empty case goes back in and the bolt closes easily. After I run it through the resize die it is extremely hard to close the bolt on the empty case. I ahve tried adjusting the die form full length to resisizing half the neck and the problem remains. Have also trimmed under recommended length. If I load the case it is hard to close the bolt but after I fire it, The empty case goes in and out easily. New factory brass goes in and out easily until I fire and resize. I am using Redding dies. I just got the rifle and dies. What is going on here.
 
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When resizing --ensure of cam-over of the sizing die and always lube the inside of the case mouth. If you hear a squeel of the expander ball as it comes out of the case mouth then there isn't enough lube and you have also changed the angle of the case neck which will give you problems in closing the bolt.
 
skhunter said:
I am loading for an 7MM STW. When I fire a shot the brass extracts easily. The empty case goes back in and the bolt closes easily. After I run it through the resize die it is extremely hard to close the bolt on the empty case. I ahve tried adjusting the die form full length to resisizing half the neck and the problem remains. Have also trimmed under recommended length. If I load the case it is hard to close the bolt but after I fire it, The empty case goes in and out easily. New factory brass goes in and out easily until I fire and resize. I am using Redding dies. I just got the rifle and dies. What is going on here.
Click to expand...

If your chamber is a bit fat then your case expands to its size. When you resize you squeeze the dia. back closer to new but in doing so you trade smaller dia for longer case length. ( the brass has to go somewhere ) Its not the OAL length, but the length from the base to the case shoulder that can make it hard to chamber. You have to set the die low enuf to push the shoulder back a couple of thous. You will feel it when you move the shoulder. Just 1/16 turn on the die ( usually involves cam over) makes it very hard to finish the stroke. Don't go overboard or you will create headspace problems.


NormB
 
I have tried resizing with the die turned in so far that you almost can't cam it over, and as much as 1/8th inch above the shellholder. It doesn't matter the bolt will barely close.
 
I have tried resizing with the die turned in so far that you almost can't cam it over, and as much as 1/8th inch above the shellholder. It doesn't matter the bolt will barely close
Click to expand...
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Make sure you are not getting case lube on the shoulder of the case.
 
Sounds like the case is either not being resized far enough down its length or you've got the die down too far and it's bulging the shoulder. That helps a lot, I know. I'd bet on the shoulder bulge. It doesn't take much of a bulge. You might be able to see it or feel it with your finger.
The die should be set up so the shell holder just kisses its bottom with the ram all the way up. Then adjust the decapper so it pops the old primer out at the same time.
"...Redding dies..." The sizer die stamped FL?
 
If it is a full length resizing die, then it is unlikely that the shoulder is bulged. That normally happens when attempting to neck size using a full length resizing die, as there is space for the shoulder to bulge into. The other situation is when seating a bullet, and a tight neck or crimp could result in a bulged shoulder.
My guess is that your resizing die is too long so that the shoulder is not being touched during resizing. Squeezing the case down makes it longer, as already said, but a long die will not push the shoulder back to correct length. This can be checked by smoking, or simply seeing if the case has lube and has been touched by the die.
 
How often have the cases been fired? If your brass is hard from shooting a few times, it may have lost ductility and will expand again on retraction from the die. The STW has a bad habit of doing this.
 
Dry inside neck. Pulling out the inside resizer is stretching the shoulder out a bit.
Clean the inside of neck and give it a bit of lube, preferrably graphite.
 
Post your measurements on a new case, a fired case & a re-sized case. Neck, expansion ring & shoulder of the case.
Something is just not adding up? I could understand if it was brass from another rifle, but fired in that chamber makes no sense.
If you have a 7mm Rem Mag die, you could back it way off to just size the neck & bump the shoulder slightly if needed.
I have a 6.5mm-300 Win Mag & a set of 264 WM dies. I have my neck die backed off for the longer 300 WM case so it just sizes the neck, & the F/L die took some trial & error, but I got it backed off & set so it just bumps the shoulder slightly allowing the case to fit the chamber nice again when a simple neck size does not do the trick.
I know things like these drive a person nuts. Good luck.
 
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