• This Forum is for adults 18 years of age or over. By continuing to use this Forum you are confirming that you are 18 or older. No content shall be viewed by any person under 18 in California.

Concentricity tool, yes or no?

Timon

Scott Wills
Silver $$ Contributor
I am about to purchase a 21st Century Concentricity tool, but I recalled a good number of people saying that theirs is collecting dust. I had a Hornady one, but it only read loaded bullet runout and frankly it rarely went past .002”. So, for the most part I stopped using it. What I really wanted to know was my unloaded neck runout and it did not do this. So this brings me back to the 21st Century. Do most of you all use one, or do you bypass this operation? Sitting here debating on pulling the trigger.
 
Another tool on the bench is always justified :) - I have something similar - ie, a runout tool that can measure any stage of the reloading process, and mine is now also just sitting there, because I'm getting bored of always seeing 0 or 0.001 on the screen. Which of course makes no sense, since I'm using T7 press and Redding Competition dies - and neither is considered accurate enough.

But, do I still need it?
YES! I just wish there were some add-ons or upgrades for it I could buy.

:)
 
I only use it to 'true up' the runout (if present) on a dummy round when getting touch depths using the stripped bolt method. A bullet with a lot of runout will give a false reading. I do have to dust it off before using as it stays on the shelf otherwise. If I was starting with hard jam as a baseline I would have to use Varsol to clean it as it would really be collecting dust. Nice unit if you feel you must have one though.
 
No - Never found it necessary to meet my goals* although I tried one once, a long time ago, and was unable to ascertain any benefit relative to group size improvement.

*Precision varmint hunting out to 300 yards,
 
If someone has one gathering dust I might buy it [if priced right]. I'm a sucker for gadgets . lol

Don ;]
 
I have the Neco. Works great. I use it when making a change in the process or adding a new cartridge to the process. I certainly don’t use it all the time.
 
If you are handy you can make one. I made my own but not as fancy as the good ones.

On a second note, does run out affect accueacy? I don't know. Someone will let us know.
 
I have the Hornady tool, which I like. I use it mostly to verify loads are less than .003 off center. It does allow you to correct concentricity with a little screw that pushes in on one side of the bullet while you measure. I do wonder about affecting the neck tension when I do this, but I like everything centered.
 
One of the biggest causes of case neck runout is if the dies expander is locked down off center and pulls the neck off center. The next would be a bushing die excessively reducing the neck diameter and it inducing runout.

The Redding bushing die FAQ tells you if the neck thickness varies .002 or more to use the expander to set the final inside neck diameter.

Bottom line, if you want to check your cases for neck runout after sizing and again after bullet seating you need a runout gauge. You need a runout gauge if you want to check the quality of the ammunition you are reloading.

The benchrest and other competitive shooters have custom rifles and dies and will tell you you do not need a runout gauge. If you have a factory rifle and use Remchester brass with off the shelf dies a runout gauge will tell you if you are doing something wrong.

That being said a full length resized cartridge is held and centered in the rear by the recessed bolt face. And the bullet is centered in the throat of the rifle with a good chance of the bullet not being tilted and starting straight down the bore. "BUT" if the case has excessive runout the bullet will be tilted and your group size will increase.

Below the hand loaded cartridge has so much neck runout the bullet is rubbing the chamber throat. If the person who posted this photo would have had a runout gauge he would have found out long before he colored the case black.

uV3Munp.jpg


Below is my favorite runout photo, its a factory loaded cartridge that got past quality control.

C4LI783.jpg
 
Last edited:
Get the gage?
For me the advice is yes.

Do you stand a zero chance without one?
No, you can still run without one, but it will be just like those debates about a chronograph... you will waste less and learn faster. The value of one is like a Moore Curve in reverse, you will use it a lot up front, then less once you understand the causes, then only to spot check batch changes on components and such here and there, so like a technology S curve in reverse.

I have owned a NECO for so long I don’t remember when I got it. I have been given a few since then and still like the NECO but admit some of the newer ones above are also very good tools and you don’t need them all. My least favorite is the Hornaday one where it checks loaded rounds and has a jack screw to “straighten”. Just my opinion that as a gage it isn’t well thought out based on where it picks up the datums and how loose the whole thing can be. My opinion is it only works well when I am actually backing it up with one of the others.

On some bases, their insurance says I must use only factory ammo. So, I have used that Hornaday tool to test if the straightening has any negatives or positives. It did help with some of their issued ammo when I had to use it at 500 - 600 yards in an AR. Best groups came from ones that were sorted straight rather than ”forced”, but forced was better than using them “as-is” with runout on the order of >0.003”. I did manage a 199-7X at one match using a batch of the ”straightened“ ones once. That ammo wold have been in the 180’s without the treatment. (BHA 77 TMK). Again, YMMV
 
The way I see it is this:
Some reloaders don’t measure for runout, ever. Some reloaders measure runout and every other measurable characteristic because it’s a possible variable that can be controlled to possibly improve group sizes. (Whether or not it absolutely shrinks groups is not the point, their standard includes all steps that even *might* shrink groups).
Some reloaders test their ammo to see if runout has a significant effect on group size, and of them, it helps for some and doesn’t help for others.

As you can see, only the first group can do without a runout gauge. That group might cover the majority of shooters here. Any other approach requires one. So decide as best as you can what you intend to do with it, but I think it’s safe to say that many (most?) shooters do not shrink their group sizes the day they get a runout gauge. But the only way to know how/if it will help you is to buy or borrow one and test.

On that note many reloaders, myself included, have one or even more runout gauges that hardly see use. So borrowing one is very reasonable.
 
After I started shooting LR BR and took my loading to an entirely new level, I found I wasn't using a runout gauge anymore. I don't think I have used one in years.......
 
I have the Hornady , testing for run-out when I started using the Redding S Type Bushing dies the tool came in handy . My run-out was horrible , switched back to my full length sizing die my run-out ranges from 0 to .002 , haven't used the tool as much , will bring it out every once and awhile. I don't compete or I would use it more often or if I was shooting long range. My max. is 200 yards that's max. for the ranges in my area.
 
I have the Hornady , testing for run-out when I started using the Redding S Type Bushing dies the tool came in handy . My run-out was horrible , switched back to my full length sizing die my run-out ranges from 0 to .002 , haven't used the tool as much , will bring it out every once and awhile. I don't compete or I would use it more often or if I was shooting long range. My max. is 200 yards that's max. for the ranges in my area.

If you were competing long range you probably not use it at all, because the equipment and processes you would develop ensure that loaded round runout isn't an issue.
 

Upgrades & Donations

This Forum's expenses are primarily paid by member contributions. You can upgrade your Forum membership in seconds. Gold and Silver members get unlimited FREE classifieds for one year. Gold members can upload custom avatars.


Click Upgrade Membership Button ABOVE to get Gold or Silver Status.

You can also donate any amount, large or small, with the button below. Include your Forum Name in the PayPal Notes field.


To DONATE by CHECK, or make a recurring donation, CLICK HERE to learn how.

Forum statistics

Threads
165,105
Messages
2,189,814
Members
78,706
Latest member
unkindyam1975
Back
Top