My Concentricity Gage

[Suasponte]

A Buddy of mine stopped by today while I was checking some 308's for Concentricity. He liked the way I was doing it and was pissed that he paid $90 for his after seeing mine! All I do is use my LE Wilson trimmer base and Case Trimmer holder to spin it on the base! I picked up Magnetic Base From Harbor freight and use a dial style gage! I screwed a piece of steel bar stock to my bench to attached the base to. You can move the magnetic base anywhere you want it and just flick the switch to on and it's stuck in place.

I really like doing it this way. The LE Wilson case trimmer holder holds it perfect and gives me a bigger area to turn the case. I used to have a Sinclair Concentricity gage but use this method only now!

If you currently have a Wilson trimmer this is a really good setup for checking run-outs.

Terry

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[xdeano]

Re: My Concentricity Gage

very nice. But how squared up is the holder? I'll have to pick up something like that. Thanks for sharing the wisdom.

xdeano

 

[distantfoe]

Re: My Concentricity Gage

<div class="ubbcode-block"><div class="ubbcode-header">Originally Posted By: xdeano</div><div class="ubbcode-body">very nice. But how squared up is the holder? I'll have to pick up something like that. Thanks for sharing the wisdom.

xdeano </div></div>


That's exactly what I was thinking. How much runout does the shell holder have by itself? I would think there's not much as the last round has very little runout.

 

[Suasponte]

Re: My Concentricity Gage

<div class="ubbcode-block"><div class="ubbcode-header">Originally Posted By: xdeano</div><div class="ubbcode-body">But how squared up is the holder? xdeano </div></div>

Its a machined piece of stainless steel that has been reemed for the proper case size! They are pretty square and Concentric! Wilson Trimmers are pretty well known for providing a nice square trimming.

Thus I would think that it holds it better than two ball bearings!

Terry

 

[Suasponte]

Re: My Concentricity Gage

Also, using the case trimmer holder it eliminates any runout you may have from a bannan shaped case. The Case holders I have are all perfectly round. Checked by putting the gage on the holder and spinning the holder. The gage did not move on any of my case holders thus they must be perfectly round. This means that what I am reading is the bullets runout only which is what I want.

Terry

 

[bellerophon]

Re: My Concentricity Gage

I envy you !
thanks for giving me ideas !

 

[Suasponte]

Re: My Concentricity Gage

Here is a little add on to the above. I have had guys ask me how I got the run-out out of my rounds. I hope this shows you how I do it! This is not the only way to do it, but it is how I do it. Hornady's new tool is supposed to be able to do it on the unit, and the is another tool made by H&H that is supposed to fix run-out too. I just do it the El-cheapo way.

Hope this helps.

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Terry

 

[phideaux]

Re: My Concentricity Gage

i use magnetic stand w/indicator but use a good V-block to put the case in. seems to work ok.

 

[bdh308]

Re: My Concentricity Gage

Terry

Where is a good place to buy the dial indicator? You mentioned where everything else was purchased but that. Or did the indicator come with the maganetic stand?

 

[SScott]

Re: My Concentricity Gage

Thanks for sharing Terry,
I spent a bunch of money on the RCBS model and my fingers have fits trying to keep the cartrige pressed down into the vee blocks, and spinning it.
SScott

 

[Pavlata]

Re: My Concentricity Gage

Thanks for sharing!

I have the Wilson .50 BMG case trimmer that I got from Sinclair's.
I also have a dial indicator setup from when I wrenched on motorcycles years ago and I have been trying to think of how I could use it to check runout.

I still need to get the .223 and .308 case holders for the trimmer. the Sinclair website states that you can use the .50 cal cutter all the way down to .22 cal, just need the other holders.

I cut 6 blocks of 2X6 and stained them the same as my loading bench. Then I drilled 2 holes in each block with matching holes in my bench. I mounted my various loading station tools on the blocks so now I can quickly change them out. I mount the blocks with 2 carriage bolts and wing nuts.

On my trimming block I can drill the bullet straightening holes.

thanks again for the tips!

P

 

[Johnsusername]

Re: My Concentricity Gage

Hi,
What Terry is using is called a drop indicator.
His has 1" travel.

MSC is a good source for all tools. Good pricing too.
In-stock stuff shipped same day.

A searched for indicator comes up with 300 results including bases, changeable back plates, test indicators.
<http://www1.mscdirect.com/CGI/GSDRVSM?PACACHE=000000126148597>

I measure stuff for a living. This would be my choice. (1/2" travel).
<http://www1.mscdirect.com/CGI/NNSRIT?PMPXNO=4463457&PMT4NO=79399030>


John

 

[Suasponte]

Re: My Concentricity Gage

<div class="ubbcode-block"><div class="ubbcode-header">Originally Posted By: bdh308</div><div class="ubbcode-body">Where is a good place to buy the dial indicator? You mentioned where everything else was purchased but that. Or did the indicator come with the maganetic stand? </div></div>

I purchase it seperately!

Look here MSC

They have lots to choose from! Ebay has them too! Just make sure you get a 1" travel with 0.001" graduations! The 1" travel just gives you room to play with setting it up. Once you have it in place it really does not matter where it reads on the dial. Just spin the case and note the movement.

Sorry John, We must have been typing at the same time! You beat me to the button! LOL.

Terry

 

[Suasponte]

Re: My Concentricity Gage

<div class="ubbcode-block"><div class="ubbcode-header">Originally Posted By: John F</div><div class="ubbcode-body">I measure stuff for a living. This would be my choice. (1/2" travel).
<http://www1.mscdirect.com/CGI/NNSRIT?PMPXNO=4463457&PMT4NO=79399030>John

</div></div>

I have a digital a keep going back to the dial. The digital seems to have lag time on the reading. The dial indicator is easier to see the bottoming out of the bullet than with a digital. JMHO!

Terry

 

[Crazy Dog ll]

Re: My Concentricity Gage

.

 

[Spooky]

Re: My Concentricity Gage

Way to go, Terry. I have that same magnetic base and also got the dial indicator from Harbor Freight (about $15 for both a few years ago). I just found some ball bearings and was studying a few ways to set it up, but your set-up looks like the bomb.

 

[Johnsusername]

Re: My Concentricity Gage

<div class="ubbcode-block"><div class="ubbcode-header">Originally Posted By: suasponte</div><div class="ubbcode-body"><div class="ubbcode-block"><div class="ubbcode-header">Originally Posted By: John F</div><div class="ubbcode-body">I measure stuff for a living. This would be my choice. (1/2" travel).
<http://www1.mscdirect.com/CGI/NNSRIT?PMPXNO=4463457&PMT4NO=79399030>John

</div></div>

I have a digital a keep going back to the dial. The digital seems to have lag time on the reading. The dial indicator is easier to see the bottoming out of the bullet than with a digital. JMHO!

Terry</div></div>

Terry,
Some digitals have lag.
I failed to elaborate.

There are more applications around a shop for an indicator and IMHO the digitals are more flexible, more reliable and don't have any internal components that can wear. You can set zero easier and use a preset dimension.

But then one could buy 3 dial units for the price of one digital.

John

 

[Suasponte]

Re: My Concentricity Gage

This is a technical addition to what I do and why I think it works better than just spinning the bullet!

The use of the case trimmer holder increases my diameter in comparison to the case diameter. The advantage of this is the increase in circumference!!! The amount or actual length that you have to rotate the case to make one full 360 degree rotation. This also translates to the dial travel itself. You say "WHY does that matter"?? Doing this makes it much more easy and accurate to find the low spot (Bottom) of the bullet. If your not leveraging perpendicular to the low spot you are just inducing more run-out by trying. I have found that using this method it takes less time to get done what I want which is to get .001 to flat liners!

See Below! Maybe this will make more sense!

At least food for Thought!

Terry

 

[steve123]

Re: My Concentricity Gage

Great idea!!!

 

[Suasponte]

Re: My Concentricity Gage

I did not do it in the video and you probably could not see it anyways due to the resolution!

When I spin the case and find the Low point of the bullet. I typically take a fine tipped marker and put a little dot on the bullet next to the drop indicator point for a visual reference. I also have a cross hair drawn on my wood holes in the blocks for a reference. This makes it easier to see that I am lifting perpendicular to the LP.

Line the dot up on the top line and lift straight up! You will find this reduces the amount of time you will have to adjust the bullet. Then as you do it you will develop a feel for how much you actually moved it.

Terry

Terry

 

[Clark]

Re: My Concentricity Gage

Ok, I tried it.

It does work, but is not as nice as my Sinclair concentricity gauge:

The main problem is the stamping of nomenclature on the case holder was rolled and not cut. The upset metal around the letters causes an erroneous run out that adds or subtracts from the cartridge run out. My Wilson equipment is very old, and was bought for $10 from a gun show junk box. Wilson might be cutting those markings with a laser now, for all I know.

 

[Suasponte]

Re: My Concentricity Gage

Have not noticed any jump due to the nomencalture on the cases!

Terry

 

[Pavlata]

Re: My Concentricity Gage

I dug out my old dial indicator tonight and tried this.
My dial indicator is metric but that is okay, google does a very quick conversion.

I ran 10 of my recent 50 BMG rounds loaded on my Hornady 50 press.
They were all at 0.16mm to 0.18mm or 0.006" to 0.007"
My dial displays increments of 0.01mm or 0.00039"

These are just my 690 gr ball plinking ammo. I am still going to drill some holes in the wood block that I have my trimmer mounted to and see if I can Zero them out.

Thanks again for posting your technique.

 

[Clark]

Re: My Concentricity Gage

OK, I sanded off the upset metal with the lathe.
It works much better now.

 

[Suasponte]

Re: My Concentricity Gage

Could just be the older style ones. I have two C&H ones that feel a little ruff to the touch. However, when I spin my cases with it there is no jump induced into the dial inicator.

Glad some of you found this helpful!

There are some more things that I do that may get posted sooner or later! Don't want to give all the tricks away!

Terry

 

[repiv]

Re: My Concentricity Gage

tag

 

[kombayotch]

Re: My Concentricity Gage

I used to do a similar thing for checking neck thickness. I would hold a neck turning mandrel in the jaws of the vice put the magnetic base on the flat anvil part of it.

You and also make a similar tool for checking for head separation. Just bend 1/16 diameter rod, hold it in the vice and align the indicator with it. Then drag the body of the case between them and watch for the needle to jump.

 

[flashhole]

Re: My Concentricity Gage

suasponte - can you please post a picture of how the gage is attached to the rod?

 

[Suasponte]

Re: My Concentricity Gage

<div class="ubbcode-block"><div class="ubbcode-header">Originally Posted By: flashhole</div><div class="ubbcode-body">suasponte - can you please post a picture of how the gage is attached to the rod? </div></div>

Here ya go!

Terry

 

[Nessal]

Re: My Concentricity Gage

I just did this today. It works!

However, I did find out that my shell holders have about 0.0005 run out. I just factor this in and subtract it from the readings that I get.

 

[commando57]

Re: My Concentricity Gage

Brilliant, very impressive!