Runout with a Redding Bullet seating die W/Correct VLD seater

[Blkrflguy]

Is brass of concern new or fire formed for your measure?
What point on seated bullets are you measuring 'bullet runout'?
\When you say: The case neck thickness varies from .005-.0015, what do you really mean? The necks are not 1.5-5thou thick, and 5thou of variance is worse than I have ever seen.

I apologize for not being more clear and I see where I could have been. You're correct. The brass has been fire formed and resized. The point I'm measuring is just above the neck of the case, say, 1/8" above, and not at the ogive.
When talking about the necks of the cases, I'm not talking about how thick they are but the varience within the thickness.

Using Redding dies, both sizing and seating, for my 6.5 PRC, and using Hornady brass, I end up with a little over a thousandth of an inch in run-out. I use their Big Boss II press and their shellholder. I employ K&M neck turning tools which includes the expand mandrel.
I would like to think that my success with concentricity is a result of my superior reloading skills, but it's really the result of superior tools.

Worst case scenario: .0045" run-out is still quite acceptable.

I was reading about concentricity somewhere the other day and there was a comment saying that match ammo tends to have no better than .003" of runout. The commenter didn't specify what manufacturer or caliber. Personally, I bought some Hornady 6/5 match before I aquired the components to start loading for this gun. Yet I didn't think to check what their runout was on those 3 boxes. I wish I would have just for a good comparison. Maybe I'll take my Sinclair run out gauge to the gun store and see how many I can measure before they tell me to leave!

 

[Blkrflguy]

What does this mean? I think there is a typo in there affecting my understanding.


Is this case neck runout measured on the od with rollers at the base and shoulder…..and no visible case defects?

your case neck od runout + neck thickness runout + seater misalignment is your minimum bullet runout. It seems like neck thickness variation is your biggest issue.

Do you use an expander ball? I find it helps runout on these no neck turn situations.

Forgot to add….how does your seater fit your bullet?

I measured the variations of the neck thickness, with a Sinclair thickness gauge. Then I set aside the ones that had a thickness variance of more than .0015". I use an expander mandrel prior to seating to push any variance to the outside of the neck so this should help to keep the bullet from being influenced by any variance. Then when I had seated bullets, I measured the bullet runout with a Sinclair runout gauge. I keep the head of the case against a small peg/pole on the gauge. The gauge has ball bearings that the case lays on. I checked the seater and it seems to fit fine.

 

[Barrelnut]

Are you using compressed loads? They can cause runout. I use the Redding competition seater too and can get runout with compressed loads. Also might just try a different bullet profile, that would eliminate the seater stem for sure.
Like others have said the setup of the die is critical because the cartridge case needs to be completely in the seating die's cartridge sleeve before the bullet starts seating.

 

[Blkrflguy]

Are you using compressed loads? They can cause runout. I use the Redding competition seater too and can get runout with compressed loads. Also might just try a different bullet profile, that would eliminate the seater stem for sure.
Like others have said the setup of the die is critical because the cartridge case needs to be completely in the seating die's cartridge sleeve before the bullet starts seating.

No not compressed. In fact my load is 40.1gn. Getting 2684 pfs from a 22" barrel. But I've seen people claiming they're loading 42.5-7gn! I don't see how.. But I've never been a guy who does compressed loads because at some point I'm going to have to dial up no matter what. I'd rather have a load that's good in January and, August. Yea i'd like to try a different bullet but with this new gun I've already done LD and found a load getting me .25-.5" and I came across 5 boxes of the Hornady 143 E-LDX bullets so, i'm kinda invested at this point. I typically shoot Begers but just couldn't find them and then found the Hornady's so...

 

[DUSTY NOGGIN]

turn necks ,anneal ,then fire em .. ya cant just expander em straight,

the cone shape of shoulder has a thicker side that ya cant turn .. thats the part that the expander mandrell wont just push over

the thicker walls of the neck go down the shoulder

they need to make a supporting die body with a camover top half that pushes expander though neck while side supported .. and then even still think fire forming would end up more centered .. due to tolerances of die versus our expectation of straight

 

[Mikecr]

I measured the variations of the neck thickness, with a Sinclair thickness gauge. Then I set aside the ones that had a thickness variance of more than .0015".

This thickness gauge, is it a ball mic?
What is the cartridge, and sizing types/amounts you're doing prior to seating?
How deep is the bullet bearing seated in necks? Deep enough to hit donut?