How do you eliminate runout

[aushunter1]

Thanks Savage.....I am doing pretty much everything you're are saying and with the same equipment except for the Lee collet die. My fired brass has anywhere from .0005-.0010 runout to start with. I run my brass through a universal decapping die first then I throw them in a tumbler and clean them. Next, after cleaning, I anneal all the necks. Then I run them through my Redding bushing die w/o the expander and decapping pin....3 strokes( rotating the brass 1/3 rotation each stroke). Then I seat the bullets with a Forster Ultra Micrometer seating die. Still getting .0025" runout

Are you loosening the bushing die decapping rod assembly slightly to allow the bushing to "free float"?

This allows the bushing to centre.


By the way-
What are you using to expand the neck??

Why are you resizing 3 times???

 

[Mikecr]

with the intended goal of improving accuracy, SD and ES I have invested in a concentricity gauge to measure runout on my brass necks and finished loads.

To begin, runout does not affect SD/ES.
And the only time runout affects shooting results is when it exceeds chamber clearances.

I noticed that you removed neck expansion from your sizing plan. This increases loaded ammo runout.
Also, what is the cartridge that we're talking about? It can make a big difference.

 

[Brett Bracken]

I'm not where I can measure it right this second but I'm pretty sure it's .333 and the bushing is .332.

 

[Brett Bracken]

Aushunter1....the bushing cap is just loose enough to allow the bushing to free float. Don't need the expander
Sizing 3 times to try to eliminate the runout
Mikecr....300 WM

 

[Savage 12BVSS]

Brett its all about the lee collet die, I use it after bumping with FL die, I use it when not shoulder bumping. Its the collet supported mandrel that keeps the neck at .0005. Till the collet die I was getting about same runout as you currently are. The straighter the bullet is the straighter it contacts the lands each time you fire, unless your running right into or against the lands already. The straighter the case neck is the straighter your seater will seat your bullets.

 

[aushunter1]

Aushunter1....the bushing cap is just loose enough to allow the bushing to free float. Don't need the expander
Sizing 3 times to try to eliminate the runout
Mikecr....300 WM

Ok, you may not need the expander in the die but you still need an expander mandrel.

Imo if your taking the dies expander out then you should be using an expander mandrel like a specific diameter K&M.

One, it helps with correct neck tension & two, it also helps to align the neck!

That's my 2 cents worth

See red below!

Brett its all about the lee collet die, I use it after bumping with FL die, I use it when not shoulder bumping. Its the collet supported mandrel that keeps the neck at .0005. Till the collet die I was getting about same runout as you currently are.

 

[rsmithsr]

what make and model of rifle.
perfect ammo will not help a poor chamber

 

[Brett Bracken]

rsmithsr.....custom built rifle..Deviant Tactical action with 26" Bartlein MTU heavy barrel. I'm already shooting 1/8/-1/4 moa groups out to 850 yds

 

[Brett Bracken]

Savage....I guess I'm going to have to try the Lee collet die

 

[aushunter1]

I'm already shooting 1/8/-1/4 moa groups out to 850 yds

Then why are you concerned about the minimal runout

 

[rsmithsr]

well if you are shooting 1/8moa groups you should save that rifle and take it to some bench rest matches... and quit worrying about run out.

why are some case .01 after firing ?
it aint adding up.

rsmithsr.....custom built rifle..Deviant Tactical action with 26" Bartlein MTU heavy barrel. I'm already shooting 1/8/-1/4 moa groups out to 850 yds

 

[Brett Bracken]

rsmithsr....not .01 but rather .0015. Yes.. the rifle shoots fine. I'm just trying to figure out why I'm inducing this darn runout (.0025) in my reloading process. Not interested in competitive benchrest shooting.
aushunter1.....yes I know it's seems I'm being a bit anal but I have my reasons. I can't shoot those 1/8 moa groups at will and I think the reason is there is something lacking in my reloading process.

 

[Trnelson]

rsmithsr....not .01 but rather .0015. Yes.. the rifle shoots fine. I'm just trying to figure out why I'm inducing this darn runout (.0025) in my reloading process. Not interested in competitive benchrest shooting.
aushunter1.....yes I know it's seems I'm being a bit anal but I have my reasons. I can't shoot those 1/8 moa groups at will and I think the reason is there is something lacking in my reloading process.

The term for what you are experiencing is tolerance stacking. Each element has a certain amount of manufacturing error. It seems that your practices are sound and that you understand how you are getting to the result that you have. A rifle that shoots a consistent 0.25 MOA is a prized piece that Is capable of placing rounds with more precision than the average shooter can aim and send

 

[Savage 12BVSS]

Brett.....lot of opinions I see, its really up to you what you want to do with your rifle. I don't shoot benchrest and still want my gun to shoot bugholes, you got the good stuff in equipment and equipment to measure your runout. You asked a simple question, yeah there are those that don't believe or care about runout. I have two guns so far that shoot one's and two's and I can see the difference in their groups with concentric ammo........for sure. Its those slight opening's in groups that you know you didn't pull. The member on here that turned me on to this just built a rifle that shoots under the one's like I wished mine would. Never heard any one complain their gun was too darn accurate

What do you have to loose? lee collet neck die at Midway $24. Sinclair expander mandrel with 30 caliber mandrel $43. at Sinclair's. You got a good rig and desire to shoot better, now its the little stuff that dials you in that final distance.......weighing brass-exact primer seating depth-eliminating runout-perfect powder weight-and sweet spot distance off lands. You know what I'm talking about. Heck I'm getting old and can tell I'm losing the fine accuracy edge I had thru life some, but you never stop learning and you never stop getting that rush when you have a good day and the groups are near perfection Good Shooting