Vern Juenke ICC unit

[AlNyhus]

Al what is your opinion do we go over board with gizmoz.

I've always been a proponent of good, basic, well worked out gear for accuracy shooting whether it's a reloading die or an action. One of the biggest misconceptions about BR shooting is that the top competitors use every latest trinket and gizmo, which is most assuredly not the case.

Good shootin'.

 

[jtm]

Thanks Al I was getting that opinion myself I think Ill unscramble my head and just shoot until I feel something is amiss

 

[TedH]

I have a Juenke and I think it defiantly sees something.
But it is one of those tools that you use a lot the first month and a lot less after that, but I still break it out every now and then

Here is what I have seen
If I test a bullet with a low deviation of say 2 then drop the same bullet on the garage floor from 3 feet, the bullet will measure different. It will usually give a higher deviation reading and the deviation may center on a different part of the scale.
This has made me worry about getting bullets in the mail. How many times does the box get dropped between here and the maker?
Cold bullets measure differently than warm bullets.

Since Jef Fowler died I have been using another manufacturers 87 grain 25 cal bullets and one thing I noticed was .
Of the bullets I tested, most all had a deviation of 3 or less, BUT there were two groups of bullets. One group showed the center of its deviation to one side of the scale and the other group showed the center of its deviation to the other side of the scale, as if the bullets were made by two different people or in two different dies.

I pick a reference bullet from the lot of bullets I am checking as a different lot or box may center in a different part of the scale.

I don't spend a lot of time testing bullets but every now and then I get the urge.
TED

 

[JayIdaho]

Do a blind test with bullets and then decide if it works.
I sorted a box of 500, .30 cal. 240 MKs. I assigned a random 4 digit number to a bag of about 15-20 of the best ones, 1 and 2 deviation units. Another bag with a different number had about 15-20 of the worst ones, 11 to 17 deviation units. Included was a sample of about 40 or 50 of the mid range ones, 4-5 deviation unts, these for working up a load. The shooter did not know which sample was best or worse.
Sent the bullets to a friend who tested in a known accurate 300 Dakota 1000 yard BR 16.5# rifle. His best groups were with the best bullets so I'm convinced that the Juenke is worth using on longrange bullets. This is before we started uniforming the meplats and sorting by ogive to boat tail.
I'm equally convinced that it is a waste of time to sort the light bullets shot at 100/200.

 

[Jimbo27]

I am confused on setting up and actually using the Junke ICC. I guess the more I read his directions the more confused I get. Does anyone know exactly how to set it up and use it?
Starting with a random bullet. If I set it and the mid after adjustments and the wheel is down the arrow moves and sows a variation. Do you leave the wheel up and set to "0" {25}?
Then the next bullet goes over to say 35 and then show say a range of 4 deviations. I guess I am really lost on this?

 

[DRNewcomb]

how do they work principle i mean is it measuring run out or somehow case thickness

I'm convinced that the Juenke machine is actually an Eddy Current NTD unit, optimized for measuring the thickness of a thin conductive layer. These sorts of machines are used in industry for measuring the thickness of silver and chrome plating over other metals. Silver over lead is mentioned in this reference. I think any mention of "ultrasonic" is either intentional or unintentional misdirection.

P.S. If it's not an eddy current device, it bypasses the obvious solution.

 

[johara1]

I believe it is a transducer very similar to the one used in checking the fuel tubes for a reactor only they a checked under water and you have run the standard ever 1/2 hour also. They measure wall thickness and check for cracks or stretched areas. To say they don't work with out using one is BS., run some test and see before making a statement. 5 divisions are on the outside of what i'm looking for those are used for short range testing,not for record rounds..... jim

 

[jimmyjam]

Want to sell it?

 

[The Pumpkin]

Want to sell it?

7 years ago?

 

[Dusty Stevens]

Put a bullet on one today, record the deviation units then test it tomorrow. You can test them each day until they pass.

 

[Jet]

Yeah I know this is an old thread

Dusty, I have found on my Juenke that the results are repeatable.

Good Shooting

Rich

 

[Immike]

Wow this is a really long debate, June 2007. Lmao half these guys are probably dead!

 

[johara1]

It is funny that of the bullets checked like Spencers, Barts and Bergers the only ones that were clear off the scale were different lots of Bergers. The other bullets were good but you will find some that are way off from the 2-3 divisions that they are running and but very few. The Bergers I had a lot that were super, the next two lots were terrible and ran the needle clear off the scale. Buy the way they sure didn't shoot either, load the good lot of Bergers and they hammered.
I think more than anything they are measuring the jacket uniformity, but the ones with low divisions shot better out of really good barrels. Average barrel or less you see less of a difference...... jim