Shoulder growing problem

[milboltnut]

JMHO, but I believe this to smell like the south end of a north bound bull. It just so happened that I needed to size some GT brass yesterday and I remembered this video. So I tried it my normal way, complete the stroke and reverse course as well as the double pump and twist method of the video. There was no difference in shoulder bump length according to my measurements.

Now, I don't believe the guy making the video to be lying. Maybe he has brass that is really work hardened and doesn't anneal? I anneal every firing so I can't say. If that's the case it seems like he needs to adjust his die so he gets the proper bump the first time. When I started reloading I didn't anneal and I seem to remember having to adjust my die more often. Now I might have to make a very small tweak after a couple firings, but then it's pretty much set for the life of the brass. I'm shooting competitions and my brass is high quality, Alpha and Lapua, and gets many cycles on it. I would think if this was to rear it's ugly head I would have picked up on it by now.

adjusting more, which does size too and annealing doesn't help. I use a feeler gauge to set the die off the shell holder, and I hold the case in the die once, one one thousand for four seconds.

Works for me and that's all that matters.

 

[MLN1963]

What is the purpose of the feeler gauge?

 

[milboltnut]

What is the purpose of the feeler gauge?

to adjust the die off the shell holder

 

[milboltnut]

ALL brass behaves differently. Consider manufactures, lot to lot, or possible issues at the factory when drawing them out.. Alot to take into consideration that we don't know about. I have variations in trimming, some need it some don't. How do you explain that? How about weight of cases ? What about case capacity? Each case varies, so whatever works at the time for each situation can be different. So what ever technique works consistently for a given situation is what needs to be done.

 

[6pakzak]

ALL brass behaves differently. Consider manufactures, lot to lot, or possible issues at the factory when drawing them out.. Alot to take into consideration that we don't know about. I have variations in trimming, some need it some don't. How do you explain that? How about weight of cases ? What about case capacity? Each case varies, so whatever works at the time for each situation can be different. So what ever technique works consistently for a given situation is what needs to be done.

I just adjust the die till I get the right shoulder bump, if I'm doing different lot I back off to make sure I don't over bump.

 

[6pakzak]

I just adjust the die till I get the right shoulder bump, if I'm doing different lot I back off to make sure I don't over bump.

The problem was the adjustment on the collet die, that's where the shoulder would grow but guys on here helped me figure it out, thanks guys. I'm less than a half turn in now after touching shell plate, I was looking at the instructions and it said to turn in 2 turns for none Lee presses, like their all the same, of course I was no where near that to begin with, probably would pop the die if I was.

 

[6pakzak]

As far as holding the case 4 seconds in the die I don't believe there is anything to be gained, if I need to bump the shoulder further I can put it through 6 times and if I don't adjust the die the shoulder will not move and if you see top shooters reloading with their motorized dillan it just goes over the case fast and it's done and if it can shoot a 2 inch group at 1000 yds that's good enough for me, not saying I can shoot that, I can't.

 

[WildRose]

I just adjust the die till I get the right shoulder bump, if I'm doing different lot I back off to make sure I don't over bump.

The height of the neck shoulder junction needs to be the same on every case you are going to use or sooner or later you're going to have a serious issue with head space.

He's right in that different brass is made to different standards of thickness which can seriously affect capacity and thence pressures but if you segregate by manufacturer you're going to eliminate most of the variation.

If you're concerned that more is necessary then weigh each case and segregate them by weight which will help you get to a point of being even more consistent.

 

[WildRose]

As far as holding the case 4 seconds in the die I don't believe there is anything to be gained, if I need to bump the shoulder further I can put it through 6 times and if I don't adjust the die the shoulder will not move and if you see top shooters reloading with their motorized dillan it just goes over the case fast and it's done and if it can shoot a 2 inch group at 1000 yds that's good enough for me, not saying I can shoot that, I can't.

That is correct. A case has a given amount of spring, how long you hold it in the die isn't going to change that.

 

[WildRose]

Laugh all you want Mil but I can't find anything known to metallurgy to the contrary.

 

[milboltnut]

what you both are missing is when you pull the case out of the die, the neck and shoulder are being forced up ward, (every action has a reaction) a bit, changing what the die was supposed to do in the first place... does that make sense?

Zak
I don't believe there is anything to be gained?? How do you know until you try ??

2 inch group at 1000 yds

And you are forgetting what kind of rig the are shooting?
Case life is foremost and accuracy is second

 

[WildRose]

what you both are missing is when you pull the case out of the die, the neck and shoulder are being forced up ward, (every action has a reaction) a bit, changing what the die was supposed to do in the first place... does that make sense?

Zak
I don't believe there is anything to be gained?? How do you know until you try ??


And you are forgetting what kind of rig the are shooting?
Case life is foremost and accuracy is second

I don't see either of us missing anything. Brass spring back is a real thing and it is limited by the hardness of the brass, no by how long you hold pressure on it.

The only thing that really changes the amount of spring back is annealing cases.

The "equal and opposite reaction" is the pressure applied to the neck and shoulder and case body shoulder junctions.

That causes brass to flow one of two ways, up, lengthening the neck or down bulging the base of the case.

Since properly annealed cases are much softer from the shoulders to the mouth the bulk of that brass flow is going to show up in slow growth of the neck.

How long you hold pressure on the die isn't going to affect that flow nor the amount of spring back you get from the brass.

 

[MLN1963]

what you both are missing is when you pull the case out of the die, the neck and shoulder are being forced up ward, (every action has a reaction) a bit, changing what the die was supposed to do in the first place... does that make sense?

Zak
I don't believe there is anything to be gained?? How do you know until you try ??


And you are forgetting what kind of rig the are shooting?
Case life is foremost and accuracy is second

The case will grow a bit when you raise the die. That's called spring back. If it is being stretched as you raise the die you are not lubing the case properly or using an inferior case lube.

I have three 6 Creedmoor rifles. I don't like changing die settings all the time so I have a set of dies for each gun. I also have dedicated brass for each gun because each chamber and headspace is slightly different. The easiest way IMO is to treat them individually and dedicate a set of dies and brass to them. Yes, it's more expensive, but I don't mine spending my kids inheritance.

 

[milboltnut]

Laugh all you want Mil but I can't find anything known to metallurgy to the contrary.

sure you can, it's common sense man.

If you form metal long enough it keeps its shape. I see it's easier to remove the case from the die after holding it for awhile, unlike in and out, and the right amount of lube REGARDLESS MLN 1963 then what lube you use makes the difference.

The case will grow a bit when you raise the die.

Ahhh yeah, the neck for sure IF you oversize the case, the shoulder get moved forward a bit if you do it too fast. The shoulder/body junction is being formed and the brass flows up.. I see that when I gauge them. There's clearance between the shoulder in the die and the case shoulder so it has room to, well, move.