Thread: Concentricity Gauges

A couple fo questions from someone who has never even seen one

Is anybody here using one?
Are there any to stay away from?
And did you see any improvements from using one?

TIA

Ha ha you don't see any improvements from using one. It just identifies the issue. You have to go back thru your process and find where the out of concentricity is being caused. Something that may not so easy. Some brands of dies induce it. Body dies for example are good at inducing it.

For some reloaders ignorance may be the best bet. Depends upon your end use how much importance you place on eliminating concentricity as much as possible.

I use a 21st Century brand gauge.

Ah I see, from what I was reading about the Hornady one you use it identify run-out and then use it to straighten out your bullet run-out?

Originally Posted by Rated M for Magnum

Ah I see, from what I was reading about the Hornady one you use it identify run-out and then use it to straighten out your bullet run-out?

Yes, I believe it works very well but it shags with neck tension in achieving straightness. Consistant repeatable neck tension is one of the biggies for accuracy.

Again, depending upon your end accuracy requirements that may or may not be an issue.

Nearly EVERY Redding FL die induces runout as you pull the Sizing button up through the neck as the taper is at the wrong end of the button

Take the spindle and button out then FL resize

put the spindle and button back in the die

Then PUSH the sizing button down through the neck as a seperate stage

Your brass will now remain as straight as your chamber left it

[QUOTE=7mmsaum;1047579]Nearly EVERY Redding FL die induces runout as you pull the Sizing button up through the neck as the taper is at the wrong end of the button

Take the spindle and button out then FL resize

put the spindle and button back in the die

Buy a Lyman M die to expand the neck solves that problem all my FL and neck dies have no button or an under sized one, I have an M die for every bullet diameter,
They also stop case stretching to some degree and keep the case mouth square.

smooth corners off your sizing button...easy to do with fine sandpaper and cordless drill
when seating...start projectile then stop and rotate case 180 degrees and continue seating...it works and difference is measurable according to much cleaverer chaps than myself.

I have the Hornady one and it works very well. Especially the feature allowing you to correct for minor misalignment

I get a bit of run out on my Forster and Redding FL dies but the shots all go through the same hole.

I get less run out with my Lyman M die but these dies are old school and often create excessive neck tension which causes the groups to open up especially once the brass has had a few firings.

Unless you are a 1000y bench rest shooter, a typical amount of run out created from top quality dies isn’t usually an issue at all and half inch to quarter inch groups are absolutely attainable.

Originally Posted by zimmer

Ha ha you don't see any improvements from using one. It just identifies the issue. You have to go back thru your process and find where the out of concentricity is being caused. Something that may not so easy. Some brands of dies induce it. Body dies for example are good at inducing it.

For some reloaders ignorance may be the best bet. Depends upon your end use how much importance you place on eliminating concentricity as much as possible.

I use a 21st Century brand gauge.

Yeah I shall remain ignorant I think ha ha

Originally Posted by Micky Duck

smooth corners off your sizing button...easy to do with fine sandpaper and cordless drill
when seating...start projectile then stop and rotate case 180 degrees and continue seating...it works and difference is measurable according to much cleaverer chaps than myself.

Loosening off the nut that holds the de-capping rod/expander so there is a little float helps too. I've never been able to prove that the two step process of rotating the case 180 degrees when bullet seating helps concentricity but it doesn't hurt either.

Originally Posted by 10-Ring

Loosening off the nut that holds the de-capping rod/expander so there is a little float helps too. I've never been able to prove that the two step process of rotating the case 180 degrees when bullet seating helps concentricity but it doesn't hurt either.

Or putting an O ring under the nut and mildly tightening on to it.

Hi all
I bought a Sinclair from the states because I wanted quality from one of the companies that originally made them.
It arrived in a week after ordering, was unpacking and it looked and worked great and when I went to put back into the box saw “Made in China”. Apparently Sinclair must be owned by Chinese. It was half the cost of getting the same item through H&F, however it does work well and I have checked it against an engineers proper instrument. I mainly use Lee collet dies and invariably get below .001 runout.

A fair bit of America must now be owned by China

Concentricity gauges are a great way of inducing sleepless nights!