Concentric bullet seating - tolerances?

I have checked my setup now, since I measure about 3-4/1000'' outrun on the bullet.

I use Harrels F/L die and when the brass has been run through this the neck outrun is less than 1/1000'' so that part of the process should be OK. However, after seating the bullet the outrun appears hence I guess I can conclude that the seater is the problem? I use a Wilson 6ppc die with micrometer top (the adjustment top from Wilson, not the Sinclair one).

Should I just try another one or what to do?
 
One thing is very important and that is the neck of the case needs to be concentric.
Soooo instead of checking just the bullet lets try a few things.

Take a freshly fired case check it for concentricity
Resize that case see if the concentricity changes after sizing being sure to check it on the neck of the case.

No if it came out of the chamber with runout and the die didnt change it then trying to bend the bullet to be concentric on a case that is not concentric in the first place is a disaster.

My dies will not straighten the cases however when firing my chamber will.
If the case comes out of your chamber after firing and the neck is not concnetric and the die wont straighten it then it is what it is HOWEVER
if it comes out of the chamber and it is off there is a serious problem.

IF everything is concentric then load the bullet but remember always check the bullet and the neck for to see if or where any run out occurs.
 
What I have done so far is this:

1) Checked neck concentricity just after firing. This is below 1/1000''
2) Checked neck concentricity after being F/L sized in my Harrels F/L die. This is below 1/1000''
3) For the fun of it, just neck-sized brass. Neck concentricity is still below 1/1000''

Then the trouble appers. Seating a F/L case the concentricity (measured more or less at the ogive) is 3-4/1000''. I tried also seating a neck sized case since this will fit the wilson seater "better", and the concentricity still appears at 3-4/1000''.

So the way I see this is that the seater must be the problem, and that it is the top of the seater that should be the problem? Or?
 
Ok so you are saying that all is ok and concentric UNTIL you seat a bullet.
Are you using only a Wilson seater die?
Is this the only seater die you have?
Can you borrow another seater and try the seating process again?
 
I use Wilson. I have got another one today to check.

But the way I understand it, 3-4/1000'' is just too much for peak accuracy from a general point of view?
 
Quote:

"Then the trouble appers. Seating a F/L case the concentricity (measured more or less at the ogive) is 3-4/1000''. I tried also seating a neck sized case since this will fit the wilson seater "better", and the concentricity still appears at 3-4/1000''. "

Try taking the measurement half way between the ogive and the case mouth. The forming of the bullet near the ogive may be in question.
 
I suppose another way to look at the validity and accuracy of what is being said is to look at who said it and their experiences.

On one hand you have someone telling you concentricity mattersI know Jackie personally and I have seen him win many many matches, not to mention the (tentative) world record he set,
And on the other hand goodgrouper...???? Nice guy and well meaning though he is.........

Then there are those with massive amounts of hall of fame points who say that concentricity is extremely important.
As a matter of interest one of the great advances in the sport was all of the correlation of centers, chamber perfectly centered bullet perfectly centered between bore and case.....

So look at the evidence for yourself.
As to gadgets concentricity is not about gadgets it is about quality equipment.
Either your dies and gun are doing their job or not.
The only gadget needed is a gauge to check the concentricity.
 
Generally, when I measure my loaded ammo (for my 6PPC) I have around .0015 runout, about .150 from the end of the case neck. As far as I can tell, this seems to be OK.

Some years ago, I did a little measuring of my Wilson seater. I wrapped scotch tape around the case neck until I could feel some resistance as I inserted it in the die, and then measured the wrapped neck. Another thing that I did was to see how far a case would go into the die base first. My conclusion was that the die was a pretty loose fit, probably because they are made to fit neck sized brass, from any chamber. Other measurements that I did convinced me that using a shallow VLD chamfer helped, as did minimal neck tension, and boat tail bullets, but since I use flat base bullets, and a lot of neck tension, I concluded that I needed a tighter fitting die. About that time, I was shooting a match at Visalia, and Don Nielson had brought several seating dies with him, to sell. He let me try one that has a .262 neck and a tighter fitting body, and my ammunition's concentricity improved to what I mentioned above, and it seemed to me that my groups were slightly improved. In any case, being an impatient sort, with my only other alternative being a custom chambered seater, I bought the die, (for $150, if I remember correctly). It doesn't have a micrometer, but I soon learned to slightly loosen the stem set screw and change the OAL of the stem and cap and then very lightly snug the set screw. I really don't miss the micrometer.

One of these days, I will probably try some of the newest short boat tail bullets that some are shooting so well. Based on earlier experience, i would guess that one advantage is that they would seat straighter on average.

One more thing, I you are having concentricity issues with a bushing FL die, a one piece die that has the correct neck dimension should resolve your problem. I know that this takes away the option of changing neck tension by changing bushings, but since I tend to only tune with powder and seating depth, for me this is not a problem. I have played around with a Hornady one piece FL die, and its neck is serviceable for a .262 chamber...very straight brass, and inexpensive.
 
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One of these days, I will probably try some of the newest short boat tail bullets that some are shooting so well. Based on earlier experience, i would guess that one advantage is that they would seat straighter on average.

Testing so far indicates that different bullet get different run-out from the same seater. As stated above my F/L die produced brass with neck run-out less than 1/1000'' (probably in the 0,0005 range) so that part of the process is fine. I have another seater to test as well which I will do with both bullets to compare if the problem repeats itself or not.

Just for the record, being a non-native english speaking person: when you say run-out is that difference from senter or maximum variation within one turn on the case? (if you understood what I meant).
 
Well lets see I named Jackie as a start. Read any number of his posts including the ones here.
Mike Ratigan who says quite a few things including "bullets will not self center"
I have not gotten that far in Tony's book but I would venture to say something similar.
Jay Lynn Gore who about 5-7 years ago would have made a clean sweep of the Gulf Coast region.
The late Shelly Davidson who taught me more than I can remember and won his fair share of wood when I knew him.

I could go on but rather just try doing a search on the words and you can find those that post here and what has been said for yourself.

I do agree with the generality of your of your statement about gadgets and shooting in general though, but not in this particular case of concentricity with the exception of anything other than a concentricity gauge.
 
Hopetobe
"maximum variation within one turn on the case? (if you understood what I meant). " would be correct.

Lets try this just for giggles
Your cases come out of the sizing die at less than .001
Check one run it up into the seater without any bullet and check the case neck again.
Then after seating the bullet check first the case neck to see if there is any change
Then check the bullet for concentricity.
Is it just the bullet that is out or does the case neck change after seating a bullet also?
 
I did a test....are we happy now?:) I intentionally bent a perfectly good round, using my H&H concentricity gauge, so that it had a indicated runout of .004, with the round supported just in front of the head, and on the bullets ogive, just back of the bullet's tip, and the indicator on the bullet right next to the case neck. I used the lever and indicator that were designed to straighten loaded rounds to make one worse than I have ever seen, from any of my equipment. Then, I chambered it, unchambered it, and remeasured it. It measured .0015 TIR. The seating depth of this round was such that the bullet was well marked, in a manner consistent with how I shoot that double radius ogive bullet, with 133. So far so good. What I forgot to do, since I have not loaded that way, is do the same test with the bullet seated so that it is not touching the rifling. As I understand it, some very good shooters load that way. Just guessing, I would think that very little to no straightening would take place when chambering a round set up this way. On a related matter, does Mr. Boyer seat into the rifling? If he does, that might explain his answer. Does anyone know if neck tension affects the degree of straightening when chambered? As for my personal preferences, I like to have things as straight as I can, but if they measure .0015 or less, I call it good. It may be a waste of time, but then again, it's my time.:)

Boyd
 
Hey goodgrouper case head first, because I always thought it should be squared. But I never have found any one else who could agree with that point. Aall I have found is basically what Mike said, though I should have tried checking all of my cases in the case trimmer. So Ill make that a priority to try out.
However Ratigan says it does no good to try to cut it square,
So Im not sure of your meaning unless you are saying bolt, chamber out of square then nothing will help and that would be true.

I read page 258. Tony never checked his rounds a sales man did.
I have never agreed with the "gadgets" as you can read above you and I agree there. I think there are added problems trying to straighten a round like stress.
I think if they are not concentric the problem should be found and solved.
Tony didnt specify here on this page whether he does or does not give any consideration to run out just the gadget. Ill read more later.

I will add that just for fun recently I tried annealing some brass and by the time I was through with them they came out .009 or more out.
I ran them through the sizing die and it didnt change a thing.
I fried them in my rifle and they were back to less than .001.
So far when I post this no one will comment on whether there is a problem with the die since it does not change anything there.
Whats your opinion?

"Mike Ratigan, Shelley Davidson, Jay Lynn Gore, and Jackie Schmidt are not in the HOF. Mike's got 8 points, and Jackie has 2. "
In reading my original post I see why you ask that? I downloaded the list and I see many more I could list. But Im not going to continue in that part of this as you seem to be trying to turn it into a petty argument.
 
I think you misunderstood the question and story about the die.
Cases were annealed which put them out of concentricty.
The dies failed to straighten them.
Firing in the rifle did straighten them to less than .001.
and running them through the die after firing them still left them at .001.
The point was that my dies do not seem to straighten or change anything either way.

If I run a bad case into my die it comes out a bad case.
If I run a good case into my die it comes out a good case.

I have not seen this with a die before.
At the moment my rifle makes good cases so its a non issue it just seems odd to me.
What is your opinion that was the question.
It does push the shoulder back .001 or so.
 
I have now complete my quest for the concentric bullet seating and found the problem, or said in another way I have got rid of the problem by buying another Wilson seater. No every case I load come out with the bullet less than 1/1000'' runout every time.

This has been a good learning experience for me, and I now know that brass fired in my rifle has necks with run-out less than 1/1000'' (I am not able to measure any). My F/L die gives my brass with neck run-out less than 1/1000'' and now my seater completes the process by giving me loaded ammo with bullets less out than 1/1000''.

One could argue if the former seater was the problem for my groups or just my skills at the bench, but I consider myself being able to shoot better than I have performed this season dispite a few victories as well. Next week will (hopefully) give some indications if the seating die was the problem or not.

I kind of also agree a bit with GoodGrouper, but also disagree. I could buy the argument about "this is probably good enough", however from my point of view I am of the opinion that several "probably good enough" might sum up to "something is wrong" and you have no clue where to start looking when you are facing the problem. That is the main reason for why I like to have everything under full control. Troubles are easier to locate when they appear.
 
I am glad to hear you found the problem

We all have different areas we deem good enough and thats fine,.

For me I think back to when I first read Warren Page's book on the Accurate rifle when they were in search of .2500 groups and aggs.

What they did and thought needed to be done then was not enough but with all the changes we now have fairly consistent .2500 aggs and better.
However if we want .1000 or less in aggs we have to find which things really are not good enough and change them.
 
I understand where you are going, no problem at all. Put to be able to put my own state of mind to peace I know that I am better off knowing that everything is as good as possible at all times hence being able to focus on the variable factors that change all the time. Tomorrow I will get the first indication if this was an improvement or not as I will spend the day at the range.

As I said, the sum of many "good enough" can (for me) aggregate to something is wrong here and I have no clue where to look. Knowing exactly my tollerances all the time contributes to solving problems quickly when they appear. It once took me almost 500 shots to understand that my barrel was not set with a proper torque - it was the last thing I checked and suspected could be wrong.

If my ammo, now with a "perfect" run-out, improves my groups that will make me happy. If not, I have learned a lot from this experience and for the future I have an easy task to complete if I want to check if they still are at the same level as they used to.

And for what it is worth my performance so far this year has been OK with few groups being catastrofic, however the number of groups in the .1's have not been that many - and that is bothering me dispite a few victories...
 
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I use Wilson. I have got another one today to check.

But the way I understand it, 3-4/1000'' is just too much for peak accuracy from a general point of view?

HTB, I've been off the net for several days and haven't read all the replies but just a thought. Excessive neck tension will cause the shoulder to cave, hence bullet runout.

Try this, seat a few flat base bullets and then check for runout. Then seat a few boat tail bullets nd check them. If the boat tails have less runout than the flat bases part of the problem may be too much neck tension.
 
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