Shoulder Bump Die?
- Thread starter Brians356
- Start date
Raythemanroe
Bullet Whisperer
Leave the bushing out of the Forster.
jonbearman
I live in new york state,how unfortunate !
Cant you leave the bushing out of your current die or is there no shoulder in the die?
Raythemanroe
Bullet Whisperer
I have the Forster bump die and after a few loading it needs full length sizing to feed well.. If I had to do it over I would have had Redding fit a die to my fire formed brass and went that route with a full length bushing die..
Ray
Ray
Grimstod
Machinist, Designer, and Shooter.
Forester can also ream out your sizing die. Just have them take enough material out of the neck and the body so only the shoulder gets bumped back.
Removing the bushing if you have a bushing die is also a really good idea. I would be inclined to go that rout.
Removing the bushing if you have a bushing die is also a really good idea. I would be inclined to go that rout.
I use JLC Precision for this. If you have them or redding make you a custom with FF'd brass, be sure to send them cases that are fully fireformed to 1thou over your actual desired dimension at the webline.
They will make a the body die size them down that 1thou, thinking that's what you want, and you will have what you want(snug fit, zero yield).
Bump only.
They will make a the body die size them down that 1thou, thinking that's what you want, and you will have what you want(snug fit, zero yield).
Bump only.
Fantastic, simply fantastic, how do you do it. I know, everyone understands, I don't. I can not bump a shoulder, I can not seat a bullet and crimp at the same time without risking collapsing the shoulder of the case, WHY!? I will answer that for you, the seating die does not have case body support.
Back to bumping the shoulder, I can not bump the shoulder without case body support. Most should understand how dumb it sounds when they say they purchased a bump die, again, to shorten the case from the shoulder to the head of the case the case body must be supported. If the case body is not supported it increases in diameter and it starts collapsing at the case body/shoulder junction, again, without case body support.
F. Guffey
^^^^^ +1 What Guffy said.
From the book "Extreme Rifle Accuracy" by M. Rattigan (Indian Creek Publishing)
"Shoulder dies do not work. You cannot push the shoulder back on the case without supporting the shoulder diameter. If you push the shoulder back without supporting the diameter, the case will get bigger in the front. When you push back the shoulder the brass gets thicker just at and below the shoulder/ body junction. If you push back and do not support the O.D., the diameter will increase, which then causes problems with interference, WHICH IS WHAT YOU WERE TRYING TO CORRECT." (Caps are mine.) " You must hold the diameter, which isn't possible when pushing the shoulder back without supporting the outside diameter."
From the book "Extreme Rifle Accuracy" by M. Rattigan (Indian Creek Publishing)
"Shoulder dies do not work. You cannot push the shoulder back on the case without supporting the shoulder diameter. If you push the shoulder back without supporting the diameter, the case will get bigger in the front. When you push back the shoulder the brass gets thicker just at and below the shoulder/ body junction. If you push back and do not support the O.D., the diameter will increase, which then causes problems with interference, WHICH IS WHAT YOU WERE TRYING TO CORRECT." (Caps are mine.) " You must hold the diameter, which isn't possible when pushing the shoulder back without supporting the outside diameter."
I never heard of a 'shoulder die' and I didn't describe bumping without body support to do so.
Body support is mild squeezing, without sizing (to cause actual yielding).
Shoulder bumping with any precision/consistency is an operation best left separate.
Bump dies should be verified locally to do just that, and they were probably fitted from a custom maker.
A body die might work for good bumping, for you, your chamber, with no other changes,,
but in general:
Body dies are not bump dies.
Bushing neck dies are not bump dies.
Bushing body dies are not bump dies.
FL dies are not bump dies.
--------------------------------------------
While you can move or mutate shoulders with these, don't think they're the same as actual bump dies.
Other different dies: Form and expander.
Custom, from any of them, is a different matter.
Body support is mild squeezing, without sizing (to cause actual yielding).
Shoulder bumping with any precision/consistency is an operation best left separate.
Bump dies should be verified locally to do just that, and they were probably fitted from a custom maker.
A body die might work for good bumping, for you, your chamber, with no other changes,,
but in general:
Body dies are not bump dies.
Bushing neck dies are not bump dies.
Bushing body dies are not bump dies.
FL dies are not bump dies.
--------------------------------------------
While you can move or mutate shoulders with these, don't think they're the same as actual bump dies.
Other different dies: Form and expander.
Custom, from any of them, is a different matter.
Brians356
Silver $$ Contributor
fguffey said:
No such process has been touted here. As I recall, only two dies have been mentioned specifically - Redding Body Die, and Forster Bump Die.
The Redding die is not a shoulder bump die, it is a full-length resizing die, with a hole at the top to bypass the neck. So it does not run afoul of the problem you describe.
The Forster is described as a shoulder bump die, but also supports the body (they say.) However, since they claim the body is not resized, they must make the body portion slightly larger, calculated to match typical chambers. Here there is some room for error, and as "mikecr" said, the real solution is to have the die customized for the actual fired case (as could the Redding Body Die.)
So, assuming the case fits the case like a glove in the body, the question them becomes how can the shoulder be set back when there is no place for the brass to go? We are dealing with one or two thousandths here, the die is not intended to positively reposition the shoulder, only to slightly bump the shoulder enough to alleviate tight bolt closure. The brass can be compressed slightly at, and just behind, the neck-body junction to allow that, even though the body is not allowed to expand farther back.
Just my thoughts on the matter. I don't anyone here believes a shoulder can be set back without supporting the case body.
It goes inward, usually thick toward thin. Given that cases taper in thickness from webs all the way to mouths, brass thickness rolls upward to donut & eventually trimmed away(with heavy FL sizing). Not so much with a thou(after springback) of shoulder only bumping.brians356 said:
I don't believe this is adequate bumping. This is merely changing shoulder angle, while the shoulder-body junction would still be left in interference length. It would not take much force to do this.brians356 said:
My shoulders are a touch rounded(hardly visible) at the shoulder-body junction, and it takes press camming over and consistent lubing to get it.
I don't really know if the shoulder angle itself is changed any.
Brians356
Silver $$ Contributor
Update:
I ordered a Redding Body Die.
In my case the 6mm Rem is for relatively low-volume, long-range varmint hunting, not competition. As such, a full-length body/shoulder resize fills the bill. The cases were subjected to somewhat high pressure during a loading process using relatively fast powder behind a heavy bullet, and I will resize them back down minimally, as determined using my incremented Redding Competition Shellholder set. After that they will probably not be subjected to such hot loads in the future, and may only need neck sizing for an extended succession of loadings.
I ordered a Redding Body Die.
In my case the 6mm Rem is for relatively low-volume, long-range varmint hunting, not competition. As such, a full-length body/shoulder resize fills the bill. The cases were subjected to somewhat high pressure during a loading process using relatively fast powder behind a heavy bullet, and I will resize them back down minimally, as determined using my incremented Redding Competition Shellholder set. After that they will probably not be subjected to such hot loads in the future, and may only need neck sizing for an extended succession of loadings.
Upgrades & Donations
This Forum's expenses are primarily paid by member contributions. You can upgrade your Forum membership in seconds. Gold and Silver members get unlimited FREE classifieds for one year. Gold members can upload custom avatars.
Click Upgrade Membership Button ABOVE to get Gold or Silver Status.
You can also donate any amount, large or small, with the button below. Include your Forum Name in the PayPal Notes field.
To DONATE by CHECK, or make a recurring donation, CLICK HERE to learn how.
Click Upgrade Membership Button ABOVE to get Gold or Silver Status.
You can also donate any amount, large or small, with the button below. Include your Forum Name in the PayPal Notes field.
To DONATE by CHECK, or make a recurring donation, CLICK HERE to learn how.