Among those of you who check concentricity (runout) of the case or loaded round, what concentricity gauge do you use? I know that these gauges at the top end can run to stratospheric prices (AccuracyOne, 21st Century, NECO, etc.)
Checking Concentricity: What Does Everyone Here Use?
- Thread starter South Pender
- Start date
I have the RCBS Case Master Concentricity Gauge and it is the Swiss Army knife of gauges and a Hornady concentricity gauge. And the problem with the Hornady gauge is you can only check loaded rounds And you are better off with a gauge that you can check case neck runout and bullet runout and find out where the runout problem starts.
And for a good basic Concentricity gauge I would recommend the Sinclair Concentricity Gauge for the average reloader with a factory rifle. You can check the case neck after sizing and bullet runout on a loaded cartridge.
Below my two Concentricity Gauges and you can't check case neck runout with the Hornady gauge. And it is important to know where and why you have a runout problem and it starts with a resized case and checking neck runout.
And for a good basic Concentricity gauge I would recommend the Sinclair Concentricity Gauge for the average reloader with a factory rifle. You can check the case neck after sizing and bullet runout on a loaded cartridge.
Below my two Concentricity Gauges and you can't check case neck runout with the Hornady gauge. And it is important to know where and why you have a runout problem and it starts with a resized case and checking neck runout.
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I recently watched a ewe toob video on Lee dies and RCBS.
The guy had several rounds of ammo was was measuring cases after running through the dies and press .
He used an RCBS concentricity gauge and the Lee dies where near perfect with .002 run-out and the RCBS was much more.
I'm still a big fan of RCBS dies, but the dial did tell the tail before and after processing live ammo.
Dont need spendy dials and jigs for home hobby unless of course you wanna spend dollars.
Rob
The guy had several rounds of ammo was was measuring cases after running through the dies and press .
He used an RCBS concentricity gauge and the Lee dies where near perfect with .002 run-out and the RCBS was much more.
I'm still a big fan of RCBS dies, but the dial did tell the tail before and after processing live ammo.
Dont need spendy dials and jigs for home hobby unless of course you wanna spend dollars.
Rob
The Sinclair one is leaps and bounds nicer to use then the RCBS gauge. The dream machine would be the 21st century model.
What I dislike great about the RCBS is the vblocks compared to the bearing surfaces on the Sinclair. Makes for much smoother rolling. Also the vblocks on the RCBS don't always lay flat so you need to modify the gauge by placing an anchor block if.yiu want to get really (or equal) measurements to the Sinclair.
What I dislike great about the RCBS is the vblocks compared to the bearing surfaces on the Sinclair. Makes for much smoother rolling. Also the vblocks on the RCBS don't always lay flat so you need to modify the gauge by placing an anchor block if.yiu want to get really (or equal) measurements to the Sinclair.
One of the biggest causes of runout happens when the expander is locked down off center and pulls the neck off center
The Lee dies expander is centered and locked down by the expander collet and is very well centered in the die.
My favorite die for low runout is the Forster full length benchrest die with the high mounted floating expander. The case neck is held and centered in the neck of the die when the expander enters the case neck. This method produces very concentric cases and the Forster die is a higher quality die than the Lee dies.
Below I fitted Forster expander and spindle assemblies to my Redding and RCBS dies to reduce neck runout.
Another method for lower neck runout is to use any make resizing die with its expander removed. Then use a expander die that expands the neck on the upstroke of the ram.
hunters home
CGN Regular
I have both the Hornady unit and the RCBS one. I prefer the RCBS unit as it can do more than the Hornady tool. These tools are great for setting up your dies to reduce run-out. I can see where the Sinclair tool with the ball bearings would be great, much easier to roll the case. I had to modify my RCBS tool to get consistant readings.
Munkey1973
CGN frequent flyer
- Location
- Regina, SK
I used to have an RCBS. It truly did a lot of things. But its performance at doing any of its functions was not even mediocre. I was so busy, making sure to keep constant pressure on the case that I wasn't really focused on reading the guage for run out testing. Takes forever t set it up too..Sold it dirt cheap (as many others were trying to sell theirs).
I was eyeing up the 21st Century (and eventually bought one last xmas) before I bought the RCBS. IMO... RCBS is not even worth a third of what they retail for. Buy once, cry once I say.... get yourself a 21st Century (or the Accuracy One)
fingers284
CGN Ultra frequent flyer
- Location
- Alberta Cowboy Ranges
I use the gun chamber...if it goes in it gets shot...
If you need to know "how much" exactly, you need a guage. You will never regret money spent on a good tool. If all you want to know is "do I have any", you can see small wobbles pretty clearly if you just roll the rounds on something really flat. A pane of glass works pretty well.
Munkey1973
CGN frequent flyer
- Location
- Regina, SK
Very sound advice. Run out greater than say 0.004-ish is often quite obvious to the naked eye using this technique. I used to use that method, however, I would still prefer to use my 21st Century Gauge as the wheel greatly speeds up the process!
If I don't take a beer & smoke break, I can easily sort 100 cases (or loaded rounds) in well less than 30 minutes with the gauge.... which is more time for me to be obsessive with other measurements.
A mirror works better. The reflection really magnifies any runout.
I use the Hornady's concentricity checker. Works for me. I use a gauge that measures within +/- 0.0005". When using Redding competition seating dies I typically get a bullet run out no greater than +/- 0.001" which the Hornady checker can tweek to get it even less.
In addition to a concentricity checker .... the biggest factor are your resizing and seating dies ... I use Redding dies exclusively and they are top shelf. Concentricity never really has to be adjusted much. I also use Lapua and Nosler brass which is extremely concentric to start with. Hornady is good too but Lapua and Nosler are second to none ... imho
