Where did the runout come from?

[ebb]

Have the cases been annealed? It would seem to me that if they wee too soft in the neck maybe the brass hasn't the stiffness it did before annealing.

 

[dstoenner]

I said I would go back and measure the neck concentricity of the loaded rounds that started this. I choose to look at only the ones that measured 4 or greater runout. There were 12 out of 46 in that group. Of those 12, 2 were .001 runout, 2 were .002 runout and the rest were .003. So seating the bullet definitely tweaked the neck in someway. Both the Redding and the Wilson are chamber seaters so the bullet can't be too out of alignment before the seating stem catches the point of the bullet and starts the process of seating the bullet. I would also point out that I seat my bullets in a 3 step process, first I seat half way, second I let off and twist the whole bullet assembly about 90 degrees and seat the bullet fully, and then third I twist the bullet another 90 degrees and bounce the ram handle twice. I have found that process to make straighter ammo than another method.

I then preformed the process of putting graphite powder in the necks. I used a new 243 brush and dipped it in my bottle I use to dip necks in for sizing if I am pulling a button through them. I then seated 10 bullets in those cases. So this would compare to the lowest loading block in my earlier picture. I got:

.001 Runout - 3
.002 Runout - 4
.003 Runout - 2
.004 Runout - 1

So this apears to have made things better. It seems to have moved 2 from 3&4 to another 2 and another 3. This looks like the solution. Based on these percentages it would mimic fully the 105. A person mentioned that the FB bullet has an expansion ring. Looks like that is the culprit and the solution is to use lubricant in the necks.

THANKS everybody for getting this understood. Now I have another tool in my arsenal of reloading.

 

[dstoenner]

Have the cases been annealed? It would seem to me that if they wee too soft in the neck maybe the brass hasn't the stiffness it did before annealing.

I thought of that also just this morning. I had them annealed at 9X firing. This is the 11th reload. Maybe after a few firings they work harden back and life is better. But I do have a solution to help for the time being.

 

[ebb]

Back a few years ago we went to shoot some of the matches at the Manatee range they all had a new tool that was all the rage, I think they called at a Bresenne tool and it fixed run out by bending the offending cartridges straight again. But many times you either bent too much or not enough so it had to be bent again and so forth. I talked to a guy at the St Louis MO range that was a national BR champion. Now just because he was a champion doesn't mean he knows it all but what he said made sense. Load it into the lands until the bullet has marks from the rifling then you know that the barrel has straightened it out and it is centered on the rifling then what does it matter.

 

[skeeljc]

I said I would go back and measure the neck concentricity of the loaded rounds that started this. I choose to look at only the ones that measured 4 or greater runout. There were 12 out of 46 in that group. Of those 12, 2 were .001 runout, 2 were .002 runout and the rest were .003. So seating the bullet definitely tweaked the neck in someway. Both the Redding and the Wilson are chamber seaters so the bullet can't be too out of alignment before the seating stem catches the point of the bullet and starts the process of seating the bullet. I would also point out that I seat my bullets in a 3 step process, first I seat half way, second I let off and twist the whole bullet assembly about 90 degrees and seat the bullet fully, and then third I twist the bullet another 90 degrees and bounce the ram handle twice. I have found that process to make straighter ammo than another method.

I then preformed the process of putting graphite powder in the necks. I used a new 243 brush and dipped it in my bottle I use to dip necks in for sizing if I am pulling a button through them. I then seated 10 bullets in those cases. So this would compare to the lowest loading block in my earlier picture. I got:

.001 Runout - 3
.002 Runout - 4
.003 Runout - 2
.004 Runout - 1

So this apears to have made things better. It seems to have moved 2 from 3&4 to another 2 and another 3. This looks like the solution. Based on these percentages it would mimic fully the 105. A person mentioned that the FB bullet has an expansion ring. Looks like that is the culprit and the solution is to use lubricant in the necks.

THANKS everybody for getting this understood. Now I have another tool in my arsenal of reloading.

"bounce the ram handle twice"??? Sounds like your seating procedure could be the cause.

I insert the bullet and case half way into the die then rotate the case some to settle the bullet on top of the case, bring the ram up until I feel the bullet contact the seating stem and then seat the bullet in one continuous slow stroke. I try to maintain a constant speed (about 1 second) with the press handle and not accelerate when the force drops as the base of the bullet exits the sized portion of the case neck. I am using a Redding Competition seater in a MEC Marksman. If the neck runout is .002" or less my bullet runout will be less than .002". That is good enough for me. I can seat 52 grain Bergers within +/- .001 OAL.