Bullet Concentricity Gauge - thoughts?

[mls204]

Does anyone use a bullet concentricity gauge to correct run-out? How much more accurate does a bullet that has been corrected shoot vs one that isn't? What do you think about these tools overall?

Just curious if they're worth it. Midway has the Hornady and Redding ones on sale until the end of the month. I don't shoot competitively but I would like to see how accurate I can get my reloads. Most of the time when I shoot it's from a bench. I will be getting into long range shooting. I understand correcting runout for AR15 plinking or carbine training would be a waste of time.

[Ferrum]

I don't use it religiously, but do use it to QC...

[Bill Steele]

I use one occasionally, more to make sure I am not missing something in my process or raw materials. I have an old fixture I bought second hand that is basically a set of V blocks and simple lever style dial indicator.

I have not shot strings back to back between say rounds measuring < .001" runout versus one with say > .002".

When it comes to accuracy, it all adds up as your groups shrink.

It is kind of like golf, the better you get, the more all the details count. Some people are happy breaking 100, others feel their round is ruined with a double bogey.

[micro911]

For my high power rifle matches, I have never used them for 200 - 300 yard ammo. I did sometimes for 600 yard ammo.

But, using M-1A with iron sights for the matches, it didn't matter much at all.

[ChrisGarrett]

Does anyone use a bullet concentricity gauge to correct run-out? How much more accurate does a bullet that has been corrected shoot vs one that isn't? What do you think about these tools overall?

Just curious if they're worth it. Midway has the Hornady and Redding ones on sale until the end of the month. I don't shoot competitively but I would like to see how accurate I can get my reloads. Most of the time when I shoot it's from a bench. I will be getting into long range shooting. I understand correcting runout for AR15 plinking or carbine training would be a waste of time.

I have a Bersin concentricity gage/fixer that does 30'06 size carts on one end and 7RM/300WM size carts on the other.

They are not cheap, but my Swiss made dial gage reads to 4/10,000ths of an inch and their varmint gage reads to 2/10,000ths of an inch.

This fixes runout after the fact, much like the Hornady device, but does so in a more precise manner, but again they're not cheap with a gage/body costing about $240 and additional bodies (223/308) costing about $180.

Some argue that one should eliminate the root cause(s) of runout in the reloading process, but not all runout is mechanically induced. A good portion of runout can be caused by the simple firing of a cartridge, causing the case to expand and contract over a few cycles, eventually taking on the shape of a banana.

If I were to buy a standard runout/concentricity gage, I'd get the Sinclair for about $115 shipped. If I had a bit more money, the Neco gage, with optional fixer block, might be a better option.

If money is no object, I'd probably get something like this one:

http://www.21stcenturyshooting.com/Concentricity_Gauge.php

I'll probably just pony up and get the second Bersin body, similar to the one in this pic. Actually, I think that is my actual unit, as pictured in the Ebay ad years back, lol:



The Bersin units come in a fitted gun type case, like the one pictured, so they're easy to take to the range with you and 'fix' stuff up.

And no, you're really not knocking the bullet back and forth, that much, where loosening 'neck tension' would be a problem. Sure, you can be a 'retard on a drum set' with it, but most adjustments are just minute nudges.

Chris

[mark501w]

I bought a Sinclair for curiosity to check the run out on my presses. They were seldom over.001" so I put it away & never used it again .

[Ahhnother8]

Does anyone use a bullet concentricity gauge to correct run-out? How much more accurate does a bullet that has been corrected shoot vs one that isn't? What do you think about these tools overall

Up to .005" of TIR, it does not matter. Use the gauge to check, and fix the process or tooling if it is more than about .003". Lots of bullet jump negates many common loading issues.

[mls204]

Thanks for the replies. It sounds like I'd benefit more from saving my money for a RCBS Chargemaster Combo 1500 instead, assuming my reloading process is solid.

[ChrisGarrett]

Thanks for the replies. It sounds like I'd benefit more from saving my money for a RCBS Chargemaster Combo 1500 instead, assuming my reloading process is solid.

I've had a CM 1500 for years and it's a nice tool. There's only one way to know how your runout, or lack thereof, is and that's to measure some of your loaded rounds and see what you see.

If you can borrow one from a buddy and measure various cartridges that you load, you'd have an idea of where you stand.

Chris

[mls204]

Yeah I agree with you 100% Chris. Too bad none of my friends reload. I would rather have the chargemaster than the gauge but it would be nice to get a few of my rounds tested.