How to improve on bullet run out

[FEENIX]

Not sure what else I can do unless buying new dies.

For what is worth, I took some measurements off 300 WSM with 215 Bergers that I loaded earlier this week with a new Lee collet neck resizing dies. It is supposedly once fired Winchester brass and it's been fireformed to my rifle's chamber (2nd firing). I am not looking for accuracy (even though I am getting well within 1 MOA without even trying that hard ) at this time, just playing around with various powders to attain velocity goal so no special brass prep was done, no 180 turn during brass forming or bullet seating, etc ...

The loaded column is as-is off the dies and the adjusted column is after using the Hornady concentricity tool. As you can see, 67 percent met the ideal spec (per Hornady's recommendation chart). Perhaps I can improve it by using the 180 trick during bullet seating next time.

Just presenting it as raw data to ponder ... nothing else.

Cheers!

Ed

 

[Mateo]

Oh & I should say, turning 180deg in a SIZING die won't change a thing.
This notion applies only to bullet seating.

Actually, it does. All got runout is caused by the expander. Rotating 180 degrees will straighten it out due to the elasticity of brass. Real world results have proved this over and over again.

 

[FEENIX]

Oh & I should say, turning 180deg in a SIZING die won't change a thing.
This notion applies only to bullet seating.

Actually, it does. All got runout is caused by the expander. Rotating 180 degrees will straighten it out due to the elasticity of brass. Real world results have proved this over and over again.

As previously noted, I am open in trying something new as I have nothing to lose but plenty to gain. If I have to I'll do it during brass sizing and bullet seating.

Cheers!

 

[Mikecr]

Well, I ended up using Hornady brass since it was the only stuff that I could buy 6 months ago..

I use the same type at least.. These are going through first or second firings...

No, I do not measure neck wall thickness or neck turn. thx

PS... Resizing neck twice helped me w/ some runout for some the outliers. I didn't do 180, but a second pass. Measurements confirm on most, not all.

Ok, part way there.
What of your sizing/sizing dies & timing with runout measure?
Where are you measuring runout?

 

[SidecarFlip]

https://youtu.be/cCrU3vvHxmM?t=242

NOTE: There's more to it than the actual video presentation, i.e., emphasis on the reloading process and equipment, like ...

https://youtu.be/jroMfxHPeYA?t=105

Exactly...

I use the Hornady gage to measure and correct runout and a Sinclair case comparator gage for necks.

I've chucked numerous pills in my LeBlond Servo Shift lathe (ABECC Class 5 spindle bearings) in high precision collets and observed no runout whatsoever.

 

[ohiohunter]

With this 180 technique do you have to size entirely or can I just turn 180 and run my ball through the neck? I really have no desire to overwork my brass, but if it reduces RO then it may be worth it.

 

[rcoody]

With this 180 technique do you have to size entirely or can I just turn 180 and run my ball through the neck? I really have no desire to overwork my brass, but if it reduces RO then it may be worth it.

I use that method with a lee collet neck sizer. don't think I would try it with a sizing die with an expander ball. You will probably be crushing shoulders

 

[Bginvestor]

Ok, part way there.
What of your sizing/sizing dies & timing with runout measure?
Where are you measuring runout?

I'll measure that tonight..

I'm measuring neck runout between edge of shoulder and forward edge of the case.

 

[Mateo]

With this 180 technique do you have to size entirely or can I just turn 180 and run my ball through the neck? I really have no desire to overwork my brass, but if it reduces RO then it may be worth it.

I size entirely for consistency. But I only push my shoulders back .001". And I anneal every third firing. So overworked brass is not an issue here. My groups are so nice I don't have any desire in changing up my regime.

 

[Mateo]

Why would you crush shoulders? You must think brass is as soft as wet paper. If that were the case then you would stretch out the brass when pulling the expander ball through it.......

 

[rcoody]

Why would you crush shoulders? You must think brass is as soft as wet paper. If that were the case then you would stretch out the brass when pulling the expander ball through it.......

you do!

my experience trying to get the expander ball back into a case that has already been sized is not good. you must be rotating the case before pulling the expander ball back through. The expander ball is where the runout comes from.

 

[Mikecr]

An expander ball 'might' contribute to your runout, not all do. And you can have plenty of runont without expanding at all. This is why I suggest that turning cases 180deg with SIZING won't work to reduce runout.
Even with SEATING, turning the case mid-operation may or may not help with runout.

In all cases, runout is addressed from the actual cause.
The #1 cause of runout is thickness variance .This is brought into play by ANY sizing(so esp. FL), and the more sizing of more thickness variance, the higher the runout.
At this cause, your expander sys could mean nothing as you might not have even sized the neck yet (for those using body dies 1st).

 

[huntnlabs]

Bullet run-out is measured off the bullet not the case neck as someone mentioned they were doing. I reduced my bullet run-out by buying a Redding Competition Seating Die. It has the floating tube guide that aligns bullet straight in the die with the mouth of the case. Checked on a Hornady Concentric Gauge, the majority of my loads are within .001" up to .002". The worst I've gotten was .003 so far. I can usually get them all under .001 with the Gauge bullet adjustment. I tried to order another one for my .17-222 from Redding but was told they don't make one for that caliber. I found Hornady does have .17-222 dies I their New Dimension Custom Grade line so I ordered the set. They have the same floating tube guide like the Redding die has. I just got them and I'm prepping brass to load now. We shall see how they do tomorrow.