Runout Question

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Kimberguy2004

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I'm loading .223 using new Lapua brass, Berger match bullets, no processing other than neck trimming and chamfer/deburr. I checked runout on the loaded rounds and at the neck, most measure .001" or less on the neck, but at the ogive, many of them measure all over the map. Is this characteristic of loads in new brass or do I need to change my seating procedure? I'm loading with a Rock Chucker, redding bushing Neck sizing die -.002" smaller than a loaded round, and a Forster micrometer seating die. I'm setting the bullet on the neck and very slowly raising the ram to seat. I'm seating with one stroke. Also, I visually compared the loaded round to one of the bullets and it looks like the neck of the case is completely contacting the bearing surface of the bullet. Should I split that up and rotate the bullet as I seat it? I thought Lapua brass would load better than that.. I'm a little disappointed. I guess I'll go out this weekend and see how they shoot..
 
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Don't know if I can help but the advice is free so you can kinda see what it's worth. I don't know what type of gage your using to measure runout but you should get almost dead nuts measuring the outside of the neck with a bushing die because it will push any variance to the inside and that is what will cause large runout. Try to set up until you can measure the inside edge of the neck. Sometimes you can tip the dial until it'll catch the inside lower lip of the case and see what you get. Or it you have an expander die that has the button properly centered then check the outside of the neck as the expander will press the variance to the outside (as long as the expander is set properly). One other thing. If you want, PM me and I'll give you my address. Send me two fired cases and I'll check them out. I have multiple seaters and bushing/non-bushing dies for the 223. One other thing to check. Make sure you have a little ring about an eight inch down from the bullet tip after seating, if not, then take out the seating stem and put a bullet up to it/in it and see if the tip is bottoming out. I have seen a lot of this.

Good luck
Hovis
 
If you are shooting this round in the AR platform you need the tension of the neck, if not then two things coem to mind about TIR, one is that the more neck tension the worse the TIR will be, some bad equipment (eg) Dies.
Now the thing about bad TIR is that it may be reduced by rotating the round by thirds when you seat the bullet. OR you could have manufactured a custom seater die.

Clarence
 
The further out to the bullet tip you measure,the more the runout is magnified. Its sort of a leverage thing. I think you will find most serious shooters measure about where the bullet would contact the rifleing. About 1/3 out from the case mouth to the bullet tip.
You have to pick a spot and stick with it for your measurements to have any meaning.
With a neck size die and pulling an expander button throught the neck you are guaranteed lots of run out.
 
It's new brass and I didn't resize it and won't until I start to have extraction issues. I am using a Redding "S" neck sizing die, but I'm not using the expander button because I was told it will screw up the concentricity of the cases as it's pulled through the case. Plus, I really don't see the logic behind sizing the neck for proper tension then opening it up again with the expander. Seems like the makings for an excercise in futility to me. I have the neck sizer set to completely size the full length of the neck. Is that too much?
What about the K&M expanding die? Is there a place for it here to help insure concentricity?
 
Might be good news here, sorry I didn't pick up on the NEW brass. If it's new out of the box you may be making better ammo than you think. After the basic brass tube is drawn, all the taper, sholder, neck and trim operations are from the outside. Even with top quality brass like Lapua some odd stuff can appear. Some BR people like to fire cases 2-3 times before they consider them ready for serious work. Blow the wrinkles out and sharpen up the sholders from the inside with 50,000psi sort of thing.
You are on the right track with .002 bullet grip and NO expanding.
Some of the runout you see might just be the usual hills and valleys in the new case body that hasn't been blown perfectly round by firing.
 
Runout

I was having the same problems with using my RCBS Rick Chucker. I was using RCBS Competiton dies and I could roll the rounds on a table top and watch the bullet runout as they rolled. Needless to say, the accuracy was not pretty.

Round one : I found that the ram had a bit of "slop" in it so I sent it back to RCBS and they re bored the way and replaced the ram (than you RCBS! as the press is over 40 years old). This made the slop go away but I still had the run out problem.

Round two: I bought a Forster Co-Ax press and Redding Competition dies and the problem was solved. Now the run out practically gone (under .001") with the same dies. The dies are Redding Competition neck bushing dies with the micrometer adjustments. The body die that comes with these dies is very useful, but I need my RCBS press to use it as the die cannot get close enough to the shoulder using the Forster press (ie the adjustable shell holder is too high).

As a side note you probably should get a VLD inside neck deburring tool if you have not already.

Just goes to show that most problems can be resolved by throwing money at them.

Good shooting,
George
 
get a K&m

Get a K&M chamfer tool to help align the bullet entry into the case. I was amazed at how much easier the bullet seated. Have you tried not tightening your dies into the press? Get an O-ring to help keep them in place but let them self align with the round as you run the round up into the die.
 
Lee lock rings have a built in O ring. I have switched to using one on my range press, that I use for my 6PPC, and have seen an improvement in runout. I don't tighten it metal to metal with the press, but just tight enough to secure the die from turning.
 
Use Rubber O-Rings with Sizing Dies for Less Run-Out

Check out the attachment. I saved it from 6mmbr.com. Thanks German! Art
 

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  • Dies; Less Run-out.doc
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Runout

I have a a Sinclair runout gage and am loading for 6BR with match bullets and Redding Comp Micro dies. On my first loading I checked the runout and it was
.0005. I was duely impressed. Second loading .0004.
I checked my 22-250 rounds that were loaded in Rem brass with Sierra Blitz's and standard Redding dies. Runout was .003. 257 Weatherby with Norma brass .002.
I can't believe it's the brass, the stuff is too consistent.
I turned the necks on mine to accomodate a tight chamber, chamfered and deburred the case mouths, but that was it.
 
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