Concentricity tool

I have heard finished bullet run out/concentricity are very important to extra accuracy.

what's the best tool for measuring these?

also neck tension? I just FL size, trim if necessary, debur and use a VLD inside neck chamfer , then run a nylon brush through each neck before charging and seating.

what am I missing? I'm not a benchrest shooter but I love accuracy.

But I like to keep it simple and fast as possible

Are you using bushing FL dies? Are you bumping shoulders .002"-.003" from fired length?

No bushing dies Jason, but I always bump shoulders back for easy bolt closing

I have the sinclair tool and it works great when I use it. I'll be honest and say that I rarely use it in general though.

^^^^ this

Mine isn't Sinclair...I did use it recently when I necked down my 6 dasher fireformed brass to 22 (yes, I've built a 22 dasher) and I wanted to see if my process was messing up the neck concentricity. It confirmed I wasn't and back in the drawer it went.

Exactly the same for me.

good to know. I guess with todays great Competition seaters, these really help. I like the RCBS with the sleeve which holds the bullet as it seats. Reminds me of an OLD OLD die I used to use for my .222 back in the early 70's. cant remember the brand. It had the sleeve with the long shell holder.


It was a Vickerman Seater.

My question is "Do you reload in a sterile dust free sealed room?" Getting pretty serious now...

I have the RCBS concentricity gauge. It works well. Like others I don't use it as often as I did when I first got it.
Normally not much run out in my loads.

But I keep it because I like gadgets.

heck yes

I use the same. I always use it when setting up a die. The sizing die is where the runout is most likely to occur and the easiest place to reduce runout.

It is a helpful piece of equipment.

Sinclair tool as well. Only use it when a problem is suspected or if I want to compare a technique, tool, or anything else.

I use a Neco Concentricity Guage, Redding Case Neck Guage, K&M neck turning tool to make all necks uniform, then redding competition bushing dies with no expander ballor pin, and redding competition shell holders to adjust how much I bump the neck, and working on getting a induction annealer as well. VLD chamfer all necks and use a RCBS chargemaster in conjunction with a Sartorius Entris124-1S and omega trickler to discharge powder. You can chase accuracy only so far before you end up going off the deep end. At the end of the day get what makes you happy. I dont know how much difference alot of what I use makes, but if I can eliminate a variable in my reloading, then why not do so.

if you use quality bullets, brass (Lapua). and dies with bushing and micrometer like those from Redding
your loaded ammo will be pretty concentric

I use Hornady concentricity tool just to check once in a while

Here are some quick and easy tips to reduce runout.

1. Remove the wire retaining snap spring that hold the shellholder in place on the ram.
Either use nothing, or use a rubber O-ring. O-rings can be purchased at auto parts stores for a few dollars for a pack.

2. When installing the sizing die, put a washer on top of the shellholder and gently apply upward pressue to the die and then tighten down the lock ring.
The upward pressure helps align the die in the threads.

3. Slightly loosen the ball sizing assembly so that it has a little bit of free play in it. This bit of play helps it self-align on the downstroke.

4. Use sleeve type seating dies. Forster invented them and Redding has a comparable one. I generally buy a basic Forster full length sizing die, but always spring for the sleeve type seater. For use with high bc bullets, remove the seating stem and make sure the tip is not hitting the inside of the stem. Forster and Redding sell stems for VLD's to correct the problem.