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Causing case neck runout?

Hello Im new to the forum and heard that this site is where there is the most experts in reloading. I really hope that someone on can help with my situation. I have use the "search" and read many of the old posts and it still does not answer.
Basically the title is my issue: case neck runout.

I noticed that my fired cases have 0 to 0.001, the needles barely moves when spun on the RCBS concentricity gauge.
I clean brass then anneal, the next day I run through the Redding type s fl bushing die with exp ball. I have also tried with RCBS matchmaster fl bushing, same bushing but no exp ball only SInclair exp mandrel. I also measure before putting through exp mandrel. All these methods increased my runout to max 0.004. I did not understand why it was increasing the runout. I tried cleaning die, honing the ball, smoothing out the part that sits on the bushing and still no luck.

I thought that it could be possibly my press. I noticed that my table is kind of tilting as it also sits on a carpeted floor. First I checked any movement on the ram and there was nothing. Then I decided to put my shell holder the other direction this way the case sits against the closed part of the shell holder because the other way I feel that the case slightly moves as the press is tilted and the shell holder opening also allows case to move. (i hope you can picture this)

After doing this I did notice some improvement but not totally removing the runout. I am getting 0.003 still increasing runout from fired cases. So after doing this there is a relation to the position of case in the shell holder inducing runout.

I wanted to try removing the spring in the ram that holds the shell holder but I have no idea how to remove also I notice the the shell holder has no movement on the ram so I doubt removing spring will do anything.

I don't understand. Even if I put the press on a very flat table I will still be getting runout. I will first try the press on a flat surface and see if this does any good.

Pls help before I totally destroy my reloading room to make a new table.
 
How did you select your bushing? Does it take a lot of effort on the press handle to pull the expander through the neck? Generally the think that causes the runout you are experiencing is that the neck is forced into a bushing or neck part of a one piece die that is so small that the expander creates a lot of pull on the case as it is pulled through the sized neck, With an bushing die you need to select a bushing such that you can barely feel the expander being pulled through the neck, and of course you need to use some kind of lube inside the neck. For the slight amount of expansion that you want to achieve something like Imperial dry neck lube would save you the problem of having to remove it.
 
Are you using a factory chamber? If so, the neck is probably expanding 0.010" or so on firing. A bushing die will induce runout if it's sizing more than 0.003" at a time, so you'll have to size in steps if you stay with bushing dies. It's much easier if you use a full-length die with a honed neck (Forster does this at reasonable cost). Choose a neck diameter that will take the neck a few thousandths smaller than your desired size, then set your final size with an expander mandrel. I combine the sizing and expansion using a Hornady FL sizer (they will customize any dimension at moderate cost) and a custom-diameter elliptical expander (its long shank is a good as a mandrel).
 
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One feature of bushing dies that I really don't like is that they can't size the entire neck; there is a short section at the base of the neck that the bushing can't touch.

If you choose to neck turn, you may be able to use a standard FL die - I reload 3 calibers and it has worked this way for me. I turn to 90% or better cleanup and the standard die sizes to a couple thousandths below where I want to end up.
 
Im going to try the FL die no bushing. Waste of all the bushings I bought. lol

I have tried locking the bushing and a tad also still no luck. I use .289 bushing I will have to try larger.

I have tired no exp ball and still get runout. I use the imperial dry neck lube and also the Vaseline like substance for the body.
 
Hello Im new to the forum and heard that this site is where there is the most experts in reloading. I really hope that someone on can help with my situation. I have use the "search" and read many of the old posts and it still does not answer.
Basically the title is my issue: case neck runout.

I noticed that my fired cases have 0 to 0.001, the needles barely moves when spun on the RCBS concentricity gauge.
I clean brass then anneal, the next day I run through the Redding type s fl bushing die with exp ball. I have also tried with RCBS matchmaster fl bushing, same bushing but no exp ball only SInclair exp mandrel. I also measure before putting through exp mandrel. All these methods increased my runout to max 0.004. I did not understand why it was increasing the runout. I tried cleaning die, honing the ball, smoothing out the part that sits on the bushing and still no luck.

I thought that it could be possibly my press. I noticed that my table is kind of tilting as it also sits on a carpeted floor. First I checked any movement on the ram and there was nothing. Then I decided to put my shell holder the other direction this way the case sits against the closed part of the shell holder because the other way I feel that the case slightly moves as the press is tilted and the shell holder opening also allows case to move. (i hope you can picture this)

After doing this I did notice some improvement but not totally removing the runout. I am getting 0.003 still increasing runout from fired cases. So after doing this there is a relation to the position of case in the shell holder inducing runout.

I wanted to try removing the spring in the ram that holds the shell holder but I have no idea how to remove also I notice the the shell holder has no movement on the ram so I doubt removing spring will do anything.

I don't understand. Even if I put the press on a very flat table I will still be getting runout. I will first try the press on a flat surface and see if this does any good.

Pls help before I totally destroy my reloading room to make a new table.
Throw the concentricity gauge in the garbage and believe the target. More time has been wasted chasing concentricity than has been gained through the years IMHO.
 
Take your concentricity gage and put it high high up on a shelf and never pull it down again. That’s where mine is and I have zero use for it.
Also, ditch the expander ball in every die you own, and finally, make sure the bushing is right side up (most have a tiny amount of taper) and lastly, make sure the bushing has a bit of free float inside the die by not locking it down.
Dave
 
Hello Im new to the forum and heard that this site is where there is the most experts in reloading. I really hope that someone on can help with my situation. I have use the "search" and read many of the old posts and it still does not answer.
Basically the title is my issue: case neck runout.

I noticed that my fired cases have 0 to 0.001, the needles barely moves when spun on the RCBS concentricity gauge.
I clean brass then anneal, the next day I run through the Redding type s fl bushing die with exp ball. I have also tried with RCBS matchmaster fl bushing, same bushing but no exp ball only SInclair exp mandrel. I also measure before putting through exp mandrel. All these methods increased my runout to max 0.004. I did not understand why it was increasing the runout. I tried cleaning die, honing the ball, smoothing out the part that sits on the bushing and still no luck.

I thought that it could be possibly my press. I noticed that my table is kind of tilting as it also sits on a carpeted floor. First I checked any movement on the ram and there was nothing. Then I decided to put my shell holder the other direction this way the case sits against the closed part of the shell holder because the other way I feel that the case slightly moves as the press is tilted and the shell holder opening also allows case to move. (i hope you can picture this)

After doing this I did notice some improvement but not totally removing the runout. I am getting 0.003 still increasing runout from fired cases. So after doing this there is a relation to the position of case in the shell holder inducing runout.

I wanted to try removing the spring in the ram that holds the shell holder but I have no idea how to remove also I notice the the shell holder has no movement on the ram so I doubt removing spring will do anything.

I don't understand. Even if I put the press on a very flat table I will still be getting runout. I will first try the press on a flat surface and see if this does any good.

Pls help before I totally destroy my reloading room to make a new table.
Describe the rifle and what it's used for. What size groups are you shooting now? I have a 6BR and a 6BRX used for GH hunting. A Rem 700 BDL and a Rem 700 ADL with Kreiger barrels on them. both shoot abt .350", a couple of 1'S and a bunch of under .300". Never measured run out. I use a Redding FL type S bushing die. Never used a ball or mandrel. I shoot 55-68 gr bullets they are seated about halfway down the neck. If your not shooting serious competition there is no reason to make things complicated. If the rifle is used for shooting at the range for fun or hunting you have to decide what the rifle is capable of and what size groups are good enough. Most of my improvments were from improving bench manners.
 
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Hello Im new to the forum and heard that this site is where there is the most experts in reloading. I really hope that someone on can help with my situation. I have use the "search" and read many of the old posts and it still does not answer.
Basically the title is my issue: case neck runout.

I noticed that my fired cases have 0 to 0.001, the needles barely moves when spun on the RCBS concentricity gauge.
I clean brass then anneal, the next day I run through the Redding type s fl bushing die with exp ball. I have also tried with RCBS matchmaster fl bushing, same bushing but no exp ball only SInclair exp mandrel. I also measure before putting through exp mandrel. All these methods increased my runout to max 0.004. I did not understand why it was increasing the runout. I tried cleaning die, honing the ball, smoothing out the part that sits on the bushing and still no luck.

I thought that it could be possibly my press. I noticed that my table is kind of tilting as it also sits on a carpeted floor. First I checked any movement on the ram and there was nothing. Then I decided to put my shell holder the other direction this way the case sits against the closed part of the shell holder because the other way I feel that the case slightly moves as the press is tilted and the shell holder opening also allows case to move. (i hope you can picture this)

After doing this I did notice some improvement but not totally removing the runout. I am getting 0.003 still increasing runout from fired cases. So after doing this there is a relation to the position of case in the shell holder inducing runout.

I wanted to try removing the spring in the ram that holds the shell holder but I have no idea how to remove also I notice the the shell holder has no movement on the ram so I doubt removing spring will do anything.

I don't understand. Even if I put the press on a very flat table I will still be getting runout. I will first try the press on a flat surface and see if this does any good.

Pls help before I totally destroy my reloading room to make a new table.
Typically, it's the expander ball being drawn through the neck. Some expander balls are more susceptible to produce this issue than some others; depends on its shape. In any case, they'll tend to more runout that what you'll see on a fire case. There are ways to mitigate it some by using a bushing and expander ball that only move the neck a couple thousandths.

If you removed the expander ball and run it through your die, you're very likely going to still see runout much like that as bushing simply tend to induce runout on their own.

Runout may not be much of a big deal . . . depending on how your chamber is designed. If you have a chamber with a lead angle of ~1.5°, runout isn't likely to be any kind of problem unless your cartridge runout is >.006" TIR. If your lead ramp is like a lot of factory barrels that are 3° or more, then runout >.003 TIR could be an issue (depending on the level of shooting you're after). IMHO

The solution that worked best for me was to simply use a FL non-bushing die without an expander ball and reamed to where the neck is only reduce to ~.002 less than where I'll want it after running an expander ball through it. My neck run out runs .001 TIR or less. How much difference that makes on paper, I don't know. My goal is to produce cases that are as uniform as possible in every way that I can't point to anything in my case prep for anomalies I get on paper; there has to be something other than my cases that's the problem. . . often it's the nut behind the trigger. ;)
 
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Take your concentricity gage and put it high high up on a shelf and never pull it down again. That’s where mine is and I have zero use for it.
Also, ditch the expander ball in every die you own, and finally, make sure the bushing is right side up (most have a tiny amount of taper) and lastly, make sure the bushing has a bit of free float inside the die by not locking it down.
Dave
^^^^^^^^^^ This to a T!…..
Especially if you’re only seeing .003 runout!..
I do pull mine down off the top shelf on new rifles to see if my chamber is concentric after that it’s off the bench!…

P.S
Welcome to the forum and best of luck
Wayne
 
^^^^^^^^^^ This to a T!…..
Especially if you’re only seeing .003 runout!..
I do pull mine down off the top shelf on new rifles to see if my chamber is concentric after that it’s off the bench!…

P.S
Welcome to the forum and best of luck
Wayne
Absolutely, only time I take my down is to check a new die. After that it's going back on the shelf above my reloading bench.
 

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