Checking run out with a Concentricity Guage

[Punisher29073]

I am not new to reloading but am trying to milk every ounce of accuracy out of my reloads. I am reloading for a 300wm using FC brass and 200gr SMKs. My method consists of this: Fire, vib. clean, neck size(RCBS neck sizer, FL size every 3rd firing after sending to Killshot44 to anneal), clean primer pocket, vib. clean, trim, uniform flash hole, chamfer, turn neck, prime, powder, bullet seat, ready to start over again.

I picked up an RCBS neck turner and a Concentricity guage. I am barely touching the necks during turning, just enough to get about 70% of the neck surface so I remove a little material as possible. Checking the concen. of the brass it is .001-.004", which I am content with. After loading with a regular RCBS seating die and checking bullet runout .1" from the neck, I am coming up with .007-.011" which seems like a lot.

1) Can I hope to achieve better with a regular die or am I going to have to get competition die to get any better?

2) Is there any suggestions to my method you have for me?

Thanks for any help.

Ryan

 

[rw496]

I found that when I use the method where you seat a little ...rotate..seat a little...rotate..etc. I get less runout. Less than .001-.004 is pretty good though. Also, I have the Hornady where you can correct runout..and it works well, but some guys say that it messes up the neck tension. Not sure if that is true or not though

 

[ZiaHunter]

For seating I use competition seating dies and have been able to maintain runout at the ogive of .0015 or less. I shoot Norma brass out of my 300 WM with very good results. I have had issues with Federal brass due to it softness and variation in neck thickness. If there is a variation greater than .001 turning will not help much. I turn my necks during my initial case prep on new brass since turning fired brass is a PITA and requires more working of the neck. When you size do you use the expander plug and what type of dies are you using? Since you are turning the necks you can eliminate the expander plug by using bushing dies. I use Redding type S FL dies and typically have runout in the neck less than .0015. By using bushing dies you can also control neck tension. Uniforming the primer pocket and debarring the flash can be done during initial case prep as well.

 

[Blackbrush]

Use FL bushing dies and FL size every time setting shoulder back only 1-2 thou. Use lots of Imperial sizing lube - be liberal with it - runout will go away and it's almost impossible to cause a lube dent w Imperial. Don't waste your time w flash holes and primer pockets - especially if you're using good brass like N or L. A Wilson seater will make the straightest ammo in the end. All of this I guarantee.

 

[Rangemaster]

For my 300 wm brass, I use only lee collet die for neck sizing. For seating I use a redding seater.
My runout stays about .001 to .003 tops. I no longer use my sizing die until like the third shooting.

 

[goodgorilla]

You can remove material with a concentricity guage?

 

[steve123]

You can remove material with a concentricity guage?

RW496 is refereeing to is applying pressure on the top side of the ogive of the bullet to straiten it in the neck to reduce run out. A little pressure doing this won't harm anything although some cartridge cases are so off that to much bending is needed to straiten them. You are better off discarding these.

I straiten them with my thumb. That way I can feel and see which are the bad ones, well the best ones to for that matter.

 

[bruddah]

It is my understanding that the concentricity gauge should be used to measure, not adjust the runout.

The Lee collet die is supposed to greatly reduce runout.