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Preferences regarding Concentricity Gauges

I used an older Forster concentricity gauge for many years with the V-block setup for both the base of the case and the bullet. I thought I could improve on this tool and picked up a Sinclair concentricity gauge. However, I found the Sinclair tool to be difficult to use--keeping the loaded round stable while turning it--and experienced the dial indicator jumping around a lot.

So I'm wondering what you guys have found best for checking runout of loaded rounds (that's the only use I'd have for the tool). I've read some good reviews of the Hornady tool that uses a hollowed holder for both the case base and bullet. This tool also evidently allows one to correct excessive runout by nudging the bullet in the case. I have some question about this latter function, though, and wonder whether by nudging the bullet around to reduce runout you might be changing the neck tension from one round to the next.

So what's the consensus (if there is one) these days about these tools?
 
There is nothing wrong with your Forster. That is what I use.
As for runout, I do check a quick sample when I first get to the bullet seating part of the process but only to verify my setup. After that I don't take the time to do it. I seat bullets in my Forster Co-Ax press and rarely do I see more than .002" total runout.
IMHO, "correcting runout on individual rounds by "nudging" the bullet may very well be worse than the runout itself.
 
I have a Sinclair concentricity gauge and a RCBS case master and both do a good job, but I had a little learning curve I had to go through. Setting the case properly in the tool adjusting the dial indicator so it applies only a light pressure, learning how to place my fingers on the case to spin were all things I had to try a time or two before I got it down.

The Hornady tool you mentioned looks pretty nice.
 
I like the NECO and the 21st Century. I have been using the NECO for years to measure runout. It does a very good job of doing that. The 21st Century is good for measuring both bullet runout and case runout.
 
I like the NECO and the 21st Century. I have been using the NECO for years to measure runout. It does a very good job of doing that. The 21st Century is good for measuring both bullet runout and case runout.

I like the NECO as well. I have the Forster/Bonanza as well. The NECO will do what the Forster/Bonanza does and more.

Danny
 
My 2 cents is a no vote for the hornady tool that measures from the rim. Dusty, for me, I think do one thing perfectly and move on. 41.0gr of powder, is that 40.95 or 41.05. It’s a hobby.
 
I’m also a huge fan of the Accuracy One gauge plus I went with the Mititoyo gauge on mine. Not cheap but dark accurate and I love how all the parts are magnetic.
 
The more important question is once you have a concentricity gauge and it's giving you reproducible numbers...what do you do with that information? Of what use is it? A number of people here will likely tell you the same thing I'm stating now, which is, my concentricity gauge gets little use. Once I figured out that my loaded rounds rarely had more than about .0015" runout, and that anything less than .003" to .004" runout (possibly even more) had little effect on precision, the tool went up on a shelf, and rarely moves from its spot.

There are certainly better ways to spend your money - i.e. on tools that will get regular and significant use. For some ideas - I like to look through the 21st Century and K&M Shooting websites. Tools for prepping brass/primer pockets and ammunition loading blocks will almost always get used regularly.

http://www.xxicsi.com/

https://kmshooting.com/
 
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I used an older Forster concentricity gauge for many years with the V-block setup for both the base of the case and the bullet. I thought I could improve on this tool and picked up a Sinclair concentricity gauge. However, I found the Sinclair tool to be difficult to use--keeping the loaded round stable while turning it--and experienced the dial indicator jumping around a lot.

So what's the consensus (if there is one) these days about these tools?

Get the coffee drinkers concentricity gauge with the rubber V blocks to spin the case on and the rubber shock mounted gauge.

I find the gauge steadies out after about 5 or 6 shots of tequila and thins down the coffee.
 
I use the RCBS Casemaster, and I find it's quite indispensable. What it really does, is allows me to figure out where any issues are in my loading process, and this changes with every single cartridge I load for. Every set of dies is unique, and they are all NOT made equal... even from the same manufacturer. I use it as consistently as any tool on my bench, and as mentioned above, if under .004" of runout, I've determined I'm pretty much good to go with any rifle that's not a bench rest, tight chamber/throated gun. I can't imagine not using it.
 
A number of people here will likely tell you the same thing I'm stating now, which is, my concentricity gauge gets little use.

I totally agree and the guys I shoot with say the same thing. I only use mine now anytime I change dies or a significant procedure or other tool or just to randomly check here and there. I guess I look at it more of a check gauge now more than a development tool. As Ned said, more or less it has a place on the bench, then it doesn’t.
 
I've had the RCBS Casemaster and the Hornady unit for over 10 yrs now. As some mentioned I used them much less as time went on. The problem I have lately is to get a consistent reading on short cases, ie 6mm br, with the RCBS unit. Is there a trick to spinning a short case. I have no problem with 308 length or longer cases but the short ones are a pain. Maybe some of you have a tip I can use. TKS
 
FWIW,
An Accuracy One Concentricity Fixture with a Mitutoyo 513-402-10 test idicator... It replaced my Sincliar Fixture with a Starrett 1" drop dial indicator. I've never regretted the change.

Regards, Matt.
 
As Stated good Dies Help ...
When in doubt I have a Sinclair.
It has a little shake , but after a couple Makers Marks , we are spot on .
 

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