Shoulder bump

[mtang45]

I want to set up my Forster FL die to bump the shoulder about .002. With the die setup per instructions and making solid contact with the shell holder it currently bumps the shoulder about .007.

Am I correct in assuming that if I shim the top of the shell holder .005 that the shoulder bump will be where I want it? Or is there a better way?

 

[mr45man]

A set of redding shell holders makes life a lot easier.
John H.

 

[mtang45]

A set of redding shell holders makes life a lot easier.
John H.

Thanks John for the suggestion. I just looked them up on Midway and they are $44 per set plus shipping. If I bought a set for each case head size I reload for, it would be a sizable investment. Easy, yes; cheap, no.

Just looking for a no cost solution to the same result ;D

 

[BoydAllen]

The instructions of die manufacturers to have the die contact the shell holder are sort of a generic thing that guarantees that the case will fit any rifle with a SAAMI chamber, that has correct headspace, at the probable risk of shortening case life. Have you tried simply backing out the die? When doing this, I would suggest that you remember that a full rotation of the die changes its vertical position by about .071", so very little rotation is needed. Having contact with the shell holder does benefit bump uniformity, and if you can fabricate a sort of shim cap for the shell holder that will stay in place, that should work fine. Another thing that you should keep in mind is that as cases are repeatedly fired and sized, they will work harden, which will require a different die setting to get to the same bump, with the increased spring back.

 

[mtang45]

The instructions of die manufacturers to have the die contact the shell holder are sort of a generic thing that guarantees that the case will fit any rifle with a SAAMI chamber, that has correct headspace, at the probable risk of shortening case life. Have you tried simply backing out the die? When doing this, I would suggest that you remember that a full rotation of the die changes its vertical position by about .071", so very little rotation is needed. Having contact with the shell holder does benefit bump uniformity, and if you can fabricate a sort of shim cap for the shell holder that will stay in place, that should work fine. Another thing that you should keep in mind is that as cases are repeatedly fired and sized, they will work harden, which will require a different die setting to get to the same bump, with the increased spring back.

BoydAllen, thanks for the information. Thats exactly what I was looking for. The tip on spring back from differing levels of work hardening of the brass is a jewell!

Thanks again!

 

[amlevin]

To answer your question about just using a shim, yes, that will work. As I see it, the advantage to shimming is that you have a positive stop at the bottom of the die and the result isn't subject to any variations in the press.

I know lots of people that have a stack of shims they use for this purpose. Make your own by taking some shim stock, placing it over a socket wrench that has a "case sized" edge, and smack it with a hammer. The socket/hammer face will cut through the shim stock. Any thinning of the stock will be at the edge of the hole and the balance of the stock will remain original thickness. When cutting off excess, just trim around the hole, leaving enough to cover the shell holder but leave a strip that can be used as a "handle".

Rather than a lot of shims for each thickness, just buy a sheet of .001" and .002" stock. Cut several shims from each. For a .005" "shim", just use two .002's and one .001.

Shims allow for precise adjustments rather than guessing how much you've backed off or advanced the die.

 

[jcampbellsmith]

When fine tuning the die, I paint a small mark on the threads and locking ring. I then loosen the locking ring and back the die out or screw it in as required. I then try resizing again and review the results and adjust the die accordingly.
Regards JCS

 

[260Ravage]

"SKIPS" die shims are darn good. One package contains all the shimms you'll need. sinclair hs got-em

 

[fr3db3ar]

The instructions of die manufacturers to have the die contact the shell holder are sort of a generic thing that guarantees that the case will fit any rifle with a SAAMI chamber, that has correct headspace, at the probable risk of shortening case life. Have you tried simply backing out the die? When doing this, I would suggest that you remember that a full rotation of the die changes its vertical position by about .071", so very little rotation is needed. Having contact with the shell holder does benefit bump uniformity, and if you can fabricate a sort of shim cap for the shell holder that will stay in place, that should work fine. Another thing that you should keep in mind is that as cases are repeatedly fired and sized, they will work harden, which will require a different die setting to get to the same bump, with the increased spring back.

This lends credance to annealing every time.

 

[Juma]

The instructions of die manufacturers to have the die contact the shell holder are sort of a generic thing that guarantees that the case will fit any rifle with a SAAMI chamber, that has correct headspace, at the probable risk of shortening case life. Have you tried simply backing out the die? When doing this, I would suggest that you remember that a full rotation of the die changes its vertical position by about .071", so very little rotation is needed. Having contact with the shell holder does benefit bump uniformity, and if you can fabricate a sort of shim cap for the shell holder that will stay in place, that should work fine. Another thing that you should keep in mind is that as cases are repeatedly fired and sized, they will work harden, which will require a different die setting to get to the same bump, with the increased spring back.

A superb description of the issue which normally is butchered by words.

 

[BoydAllen]

 

[Bob3700]

If you set up your die with an o-ring under the lock ring. Now set up the die for that .002" bump. Now with a gauge that measures base to neck datum, you can move the die up or down making small adjustments. The o-ring will help the die stay in place.

Bob