concentricity issues with redding collet neck sizing die?

Diablo7101

Diablo7101

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Like the title says, the first stage of sizing my .308 brass I am getting upwards of 7 thou deflection after neck resizing with a redding collet neck sizing die.
Where should I start looking for the problem? Collet size, decapping/expander rod?
Any insight would be helpful as I just started using the collet dies and am not that familiar with them yet.
I lube inside and outside of the neck each case sparingly.
 
I was unaware that Redding made a collet die. Lee makes a collet, Redding makes a bushing die. If you are talking about a Redding, first, make sure your die is set up properly (according to mfr's instructions). Second (and this is also in the instructions), make sure the bushing is able to float a little (bushing retainer backed off about 1/32" - just enough so you can hear the bushing rattle slightly when you shake it).

In my experience, there's not a die in the world that will compensate for improper set up or a press that is wonky in the first place (ask me how I know). I hope this helps a bit.

Rooster
 
358Rooster said:
I was unaware that Redding made a collet die. Lee makes a collet, Redding makes a bushing die. If you are talking about a Redding, first, make sure your die is set up properly (according to mfr's instructions). Second (and this is also in the instructions), make sure the bushing is able to float a little (bushing retainer backed off about 1/32" - just enough so you can hear the bushing rattle slightly when you shake it).

In my experience, there's not a die in the world that will compensate for improper set up or a press that is wonky in the first place (ask me how I know). I hope this helps a bit.

Rooster
Click to expand...

He said it all
 
358Rooster said:
I was unaware that Redding made a collet die. Lee makes a collet, Redding makes a bushing die. If you are talking about a Redding, first, make sure your die is set up properly (according to mfr's instructions). Second (and this is also in the instructions), make sure the bushing is able to float a little (bushing retainer backed off about 1/32" - just enough so you can hear the bushing rattle slightly when you shake it).

In my experience, there's not a die in the world that will compensate for improper set up or a press that is wonky in the first place (ask me how I know). I hope this helps a bit.

Rooster
Click to expand...

Your right, it's a bushing die...my mistake. I've gone over the setup a dozen time and it's all good as per instructions. I even set up an old lee press I have kicking around and got the same results. Could both presses be wonky? I'm using a rcbs now.
 
Could be that your mandrel is cocked off a bit, causing the necks to form or pull off center. It's been quite a while since I set up a Lee collet, so I can't cite any advice for that right now.

How has the RCBS produced compared to the Lee? If results are the same, I'd look at a different variable.

Rooster
 
Resize the case with a full length resizing die with the expander ball removed and measure the runout and see if it is less than the bushing die.

If your cases have unequal case wall thicknesses they will expand more on the thin side of the case when fired and warp and become banana shaped.

A neck sizing bushing die "floats" and will not straighten a warped case, a full length die will align the body and neck of the case "BUT" a warped case will never have low runout.

And I have had my RCBS Rockchucker press since 1973 and might be a little worn, "BUT" I would never blame the press as long as the die makes firm contact with the shell holder and the case can move and float in the shell holder.

I use Redding Competition shell holders that vary in height, this way the shell holder can always make hard contact with the die meaning press cam over. I also use a rubber o-ring under the dies lock nut that allows the die to float and self center in the press theads.

Bottom line, a neck thickness gauge and a runout gauge will help find the problem between bad brass and die alignment problems and you will never fix bad brass.

Below is a NECO case gauge and it describes the problems you can find with improperly made brass. I do not have this specific gauge BUT there is a reason why competitive shooters buy Lapua brass and not American made cases.
So again you need to find out if you have a die alignment problem, a shell holder problem or a problem with the brass. And to find the answer you need the correct gauges and a neck thickness gauge and a runout gauge is a must.

runout_zpsfe87d011.jpg
 
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Have you mesured the run out from a fireform case before passing it thru the neck sizing die ?

If not, do it and report the run out .

Mush
 
bigedp51 said:
Resize the case with a full length resizing die with the expander ball removed and measure the runout and see if it is less than the bushing die.

If your cases have unequal case wall thicknesses they will expand more on the thin side of the case when fired and warp and become banana shaped.

A neck sizing bushing die "floats" and will not straighten a warped case, a full length die will align the body and neck of the case "BUT" a warped case will never have low runout.

And I have had my RCBS Rockchucker press since 1973 and might be a little worn, "BUT" I would never blame the press as long as the die makes firm contact with the shell holder and the case can move and float in the shell holder.

I use Redding Competition shell holders that vary in height, this way the shell holder can always make hard contact with the die meaning press cam over. I also use a rubber o-ring under the dies lock nut that allows the die to float and self center in the press theads.

Bottom line, a neck thickness gauge and a runout gauge will help find the problem between bad brass and die alignment problems and you will never fix bad brass.

Below is a NECO case gauge and it describes the problems you can find with improperly made brass. I do not have this specific gauge BUT there is a reason why competitive shooters buy Lapua brass and not American made cases.
So again you need to find out if you have a die alignment problem, a shell holder problem or a problem with the brass. And to find the answer you need the correct gauges and a neck thickness gauge and a runout gauge is a must.

runout_zpsfe87d011.jpg
Click to expand...

Thanks for the info...there are points to start looking at. I have a sinclair concentricity guage and a Innovative Technology head space guage but no guage for brass thickness. I am using factory remington brass for my hunting rounds, that's what I am working with now. I have 100 new lapua brass for a precision 308 I have but wanted to get everything right before I messed them up.
 
Diablo7101 said:
Thanks for the info...there are points to start looking at. I have a sinclair concentricity guage and a Innovative Technology head space guage but no guage for brass thickness. I am using factory remington brass for my hunting rounds, that's what I am working with now. I have 100 new lapua brass for a precision 308 I have but wanted to get everything right before I messed them up.
Click to expand...

With a neck thickness gauge you will have a ball park idea on how uniform the case wall thickness is and a uniform case will have less runout. As an example cheap .223/5.56 ammo is made from cases that are seconds and can have large variations in case wall thickness, and these type cases will give you the most headaches with neck runout.

Below I have the RCBS Case Mastering Gauge, with it I can check runout and case wall thickness. I also have the Hornady concentricity gauge that can be used to straighten these cheaper cases.

runout003_zpsd19b7cc3.jpg


I also have the Sinclair case neck thickness gauge below and one quick 360 degree twist of the case will tell you the variations in neck thickness. The reason I like this gauge is you "SEE" the variations by the gauge dial indicator movement instead of taking many readings with a ball mike. (and then counting on your fingers) :eek: I have both the RCBS and Sinclair gauge sitting on my reloading bench when setting up my dies and then checking the runout and trying to reduce the runout to the minimum.

reddingneckgaugex250_zps88727434.jpg
 
358Rooster said:
Hey Biged; gold as always. Great info!
Click to expand...

"All the information in the world is written in books and all you have to do is read." Meaning I put my pants on the same way as all of you do "BUT" you would be surprised how much information is in the front part of your reload manuals and other sources. (RTFM) ;)
 
bigedp51 said:
"All the information in the world is written in books and all you have to do is read." Meaning I put my pants on the same way as all of you do "BUT" you would be surprised how much information is in the front part of your reload manuals and other sources. (RTFM) ;)
Click to expand...

i just assumed it was a bonus fire starting paper, maybe i will start reading that part some time :)
 
I almost always get straighter cases with FL dies than my neck dies. I've even replaced my neck bushing dies with Full length bushing dies. I can prove that anytime.

Where bushing dies have a chance is on tight chambered rifles with premium sorted or neck turned brass. When the neck only has to be massaged a couple or four thousandths it doesn't move much. Even then there is no particular reason to believe that a straight neck is going to be centered. On factory rifles or even somewhat tighter custom chambers with ordinary brass a bushing die is a waste of money. I wish I would have spent the considerable amount I put into neck bushing sets into quality brass and more barrels.
 
I would start by sizing a fired case without the expander ball, it can be a bad culprit. Also, depending on how far down you are sizing the neck you might need to do it in two steps. Redding has info on that issue on their website.

Unless there is something wrong with your bushing it would be pretty unusual for a Redding bushing die to introduce 7 thou runout on a straight case based solely on the bushing (I.e. not caused by something else like the expander). If you are having the same problem with two different presses that tells me you need to look at the die.
 
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