Concentricity Gauge?

Discussion in 'Handloading and Reloading' started by Wyo82, Dec 2, 2021.

  1. Wyo82

    Wyo82 Member

    Joined:
    Dec 28, 2020
    Messages:
    139
    Location:
    NE Wyo
    How many of you use a concentricity gauge? Those that do, do you notice much of a difference in your groups or accuracy?
     
    South Prairie Jim likes this.
  2. jmorris

    jmorris Member

    Joined:
    Sep 30, 2005
    Messages:
    18,792
    I have built a couple different ones. I really use them more for process setup. Once I have components, tooling and processes happy with one another there isn’t much use in them as results are consistent at that point.

    They are a great tool to see what effect changes you make have though.
     
    Walkalong and 1066 like this.
  3. Bcwitt

    Bcwitt Member

    Joined:
    Dec 22, 2020
    Messages:
    553
    Location:
    Pennsylvania
    I use one to sort bulk ammo. You can pick the fliers out.
     
    Chuck R. likes this.
  4. Walkalong

    Walkalong Moderator Staff Member

    Joined:
    Nov 20, 2006
    Messages:
    69,667
    Location:
    Alabama
    Like @jmorris, I use one to check set up and make sure my chosen die/brass/bullet combo is loading straight ammo, tweak if needed, which might mean a different die or dies. Then be happy and work on your shooting.

    It's going to be very hard to beat the Sinclair unit, especially when on sale. I turned mine into a brass marker for match ammo as well. I also have a 21st Century concentricity gauge, not impressed (and their stuff is usually very good, absolutely love their hand primer), and an old NECO, plus an Accuracy One gauge (Superb, but pricey). If I were to do it allover, I would just wait for the Sinclair to go on sale and get it.

    Sinclair Concentricity Gauge @ 50%.JPG Sinclair Concentricity Gauge Mod Pic 6.JPG
     
    Last edited: Dec 3, 2021
    marchboom, dartor and Akula69 like this.
  5. jmorris

    jmorris Member

    Joined:
    Sep 30, 2005
    Messages:
    18,792
    The style above is pretty versatile. You can move the bearings so they are contacting the body of the case, a spot in the shoulder or the neck.

    070E5166-A5C0-4743-99B9-AD8A1BDE049E.jpeg
    CD66EA5C-F82A-4E52-9692-72F94B6DB9D2.jpeg

    Might give you some information, others will not, if you have something you cannot explain going on. You can check fired cases and re check every step of the way to see if and where error is imparted to the case. Narrowing the problem to the particular step that caused it. This is the most helpful use of them for me.

    I also made an attachment for mine where I can slide a case over the mandrel and measure wall thickness of cases without causing any harm. Another helpful tool but has nothing to do with runout.

    9740B27E-FE18-42AE-85B9-411BF1DA3FBA.jpeg 4EF2CFBF-BC49-4BCC-A15D-E0A0D0FFB47A.jpeg

    As far as shear speed and ease of use, this style wins.

    1DF064E1-C23D-49F5-9F68-605CB28F7ABE.jpeg

    It cannot be used to check just a fired case, then again after sizing, again post expanding, etc; however, if you are wanting to check every loaded round and have a bunch of them, it doesn’t take long to realize it beats the others in this one use.
     
  6. South Prairie Jim

    South Prairie Jim Member

    Joined:
    Apr 18, 2019
    Messages:
    3,072
    Location:
    Montana
    Good information on this thread, for whatever reasons I have not seen any difference on paper out to 600 yards. I have not tried a side by side at 1000 however I would yield to someone who has results at long range.
    Good dies and set up are the key imo
     
    Chuck R. likes this.
  7. Chuck R.

    Chuck R. Member

    Joined:
    Jan 23, 2005
    Messages:
    3,743
    Location:
    Leavenworth, KS
    \

    That's because like all other things; SDs, ES, concentricity, etc. actual accuracy trumps statistics (to a point).

    I've also got the Sinclair unit and it works well. I use it for initially setting up dies etc. and then to cull "rejects" with excessive run out. "Rejects" aren't discarded, they get their primers marked with an alcohol pen and shot art shorter distances.

    I honestly think an awful lot of the precision loading steps are incremental improvements, and some of it is psychological to remove excuses... I know what my ammo/rifle can do, so in the end it's got to be me...
     
    Walkalong and South Prairie Jim like this.
  8. lightman

    lightman Member

    Joined:
    Feb 7, 2011
    Messages:
    2,729
    Location:
    england,ar
    Another Sinclair owner here. When I started using this tool I found out what was causing the flyers that I was manfully taking the blame for! If your bullet is seated crooked or your case necks are bent those things will open up your groups. This tool helps you to find the cause and lets you change your process.
     
    Walkalong likes this.
  9. Thomasss

    Thomasss Member

    Joined:
    Aug 3, 2020
    Messages:
    739
    Location:
    Wisconsin
    Industry standard for bullet concentricity is .002. With my gauge I can get that down to less than .001.
    It does help. I have a 1970 Rem 700 in 30.06. I consistently shoot .75 MOA at 100 yards.
     
    sparkyv likes this.
  10. jmorris

    jmorris Member

    Joined:
    Sep 30, 2005
    Messages:
    18,792
    I can say one thing I found out after I built a few of the fixtures and went back over loads that had been worked up.

    I had some 22 Hornet loads that shot pretty good (.3” for 5 @ 100) but I knew we’re not perfect as a machinist eyes could see the run out. After fooling around with them for awhile, I realized that once the ammunition was chambered, it was fixed. Made me wonder how many of the “load to the lands” people were converted because they couldn’t seat a bullet straight.
     
    Walkalong and South Prairie Jim like this.
  11. Varminterror

    Varminterror Member

    Joined:
    Jul 17, 2016
    Messages:
    10,083
    I’m with @South Prairie Jim. You had better be able to shoot pretty stinking, ridiculously, incredibly, disgustingly small groups before you spend time sorting ammo by concentricity, otherwise it’s not spending time, it’s wasting it. I can’t shoot the difference in ammo to make sorting by concentricity fruitful - money is better spent to buy better dies and skip the time wasted rolling cartridges.

    I have the old Hornady tool, the Sinclair, and just got the new Hornady tool. For me, they are toys to tickle my curiosity and take up shelf space, not critical tools in my reloading process. I shoot plenty small for the tasks I pursue, and these have no stake in that claim.
     
  12. Wyo82

    Wyo82 Member

    Joined:
    Dec 28, 2020
    Messages:
    139
    Location:
    NE Wyo
    Thanks for the info everyone! What actually brought this up is 1) seeing them always in stock when nothing else was/is, 2) my father in law and wife were asking if I wanted or needed one for Christmas, and I wasn’t really sure if it would be money well spent or useful. I mostly reload for hunting ammo and some plinking rounds, so these posts cleared it up for me! Thanks again
     
  13. South Prairie Jim

    South Prairie Jim Member

    Joined:
    Apr 18, 2019
    Messages:
    3,072
    Location:
    Montana
    Your probably right, and when you think about sizing and chambering as with the stripped bolt method we are .002 bump after the bolt drops freely the headspaced cartridge isn’t touching the chamber shoulder and bullet seems to self center into the throat so we can’t have too much influence brewing unless we subscribe to in bore yaw and that theory.
     
    jmorris likes this.
  14. jmorris

    jmorris Member

    Joined:
    Sep 30, 2005
    Messages:
    18,792
    I agree with this up to the point of thinking money always solves problems or even knowing if you have one without the tool.

    If you wanted one to gain a little knowledge, I have spent more money to learn less in the past….

    On the scale of importance, I would put one ahead of neck turning or primer pocket uninformer. Aka, not very high on the list of importance and far from a necessary tool.
     
    Last edited: Dec 4, 2021
  1. This site uses cookies to help personalise content, tailor your experience and to keep you logged in if you register.
    By continuing to use this site, you are consenting to our use of cookies.
    Dismiss Notice