Concentricity Gauges

[CWLONGSHOT]

Do you have one?

Do you use one?

Do you have a Favorite?

I have used a Sinclair and liked it. Bought a RCBS but dont love it. I got some gauling on the V-blocks after a few years of use and RCBS sent me replacements. I looked for a replacement.
I picked up a Redding Slant Deck tool. This uses hardened taperd pins instead of V blocks or ball bearings like the RCBS or Synclair tools.
I like the ball bearings.

I wondered why not use actual bearings as they would allow cases to roll efortlessly with out friction. But they would introduce or show the inaccuracy of the bearing. By using a static surface there was zero inaccuracy.

I saw some tools recently pop on eBay for attractive costs. But beware they are 3D printed. This is no good as it is not rigid and introduces runout simply from flex.

I ordered a "BED" and found it a wuality printed piece. But still no good as it had flex. Remember we are measuring wanting numbers like .001. Dust and debris on pieces can be .0005 or more. And flex can be 2-3x that amount.
Im wondering what you guys use and like and why.

CW

 

[Gary]

Got one! Hornady; hardly use it.

 

[358156 hp]

Some of the big kids I know use this one: https://21stcenturyinnovation.com/b...entricity-gauge-with-indicator-cnc-gg-wth-ndc

 

[Rick H]

I have a unit I purchased from Sinclair. I'm not sure of the brand. Haven't used it in years. With rimless cases I can learn all I need with a quick roll of the ammo on a glass pane. Any significant runout is instantly apparent.

 

[Trapperscott]

I have one I purchased from Sinclair. I’ve used it several times chasing down issues. Just recently I had an issue with a Marlin 35 Remington. I could not get it to shoot worth a hoot. 4-5 inch groups at 100. I checked everything I could think of and couldn’t figure it out.

I was standing at my bench scratching my watch and winding my butt trying to figure out what I was doing wrong when I saw my concentricity gauge sitting at the back of a shelf. I checked a loaded round and found that it had .011 runout. After checking several more I had as much as .013 runout after the ogive. I checked a sized case and had .007 runout on the neck. Those were loaded with Lee dies. In the trash those dies went.

Ben came to the rescue with a set of Redding dies which I finagled out of him. Now my loaded rounds have .000-.002 runout on the bullet after the ogive. Now if I do my part it shoots under an inch at 100.

 

[Ben]

All is well that ends well.

Ben

 

[Michael]

I have never used one nor a bore scope. All of my ammo has zero run out and is perfectly straight. Also and none of my barrels have any lead, copper/jacket fouling. I size cases with vise grips and seating bullets with a claw hammer, they also work quite well together has a bullet pulling combo.

In all honesty, they are useful, like a bore scope, another rabbit hole I could very easily sucked into. My wife thinks I am already borderline OCD, and did I mention that uniformity is a beautiful thing.

 

[jannickz]

I understand you're looking for feedback on case neck gauging tools and your experience with different brands and types.

• Ball Bearing Gauges: These offer smooth operation and minimize friction, but their accuracy can be affected by bearing quality and potential inaccuracies within the bearing itself.
• Tapered Pin Gauges: These provide a static measuring surface, eliminating bearing-related inaccuracies but potentially sacrificing smoothness compared to ball bearings.