Concentricity Troubles

[ArmyCW]

I received my RCBS concentricity gage in the mail today from MidWayUSA opened and put together. So, I checked a bunch of brass around the neck area of once shot brass that has been resized and deprimered. I found a couple with very little variation, +.002 to -.002 on the gage. Some as bad as +.005 to -.004, usually most in between.

Wondering what the resizer would check out, so took it apart and check the 3/16 threaded pin and it out +.002 to -.002, just the pin!!
Put the gage on the neck resizer and its out of tolerance too.
+.003 to -.002 on the gage. Wow. I'd say that is trouble to begin with
so I have ordered a replacement decapping rod and with resizer/expander. Definately will check it when It gets here.
This is most likely some of my accuracy problems as noted in prior posts.
Kenny

 

[Ol` Joe]

The insanity begins.....
:twisted:

 

[JD338]

The insanity begins.....
:twisted:

Well said Ol' Joe.

JD338

 

[BK]

Speaking of concentricity guages, what does everybody like as far as brands? I am starting to think I need a new piece of gear.

 

[rick smith]

I use the Neco and Sinclair. Tried the RCBS but didn't like it.Rick.

 

[big rifle man]

For concentricity purposes I use a Bersin tool. Made in Norway and works llike a charm. It consists of an aluminum block with a chamber matching a number of calibers using the same type of case cut through the center. both sides have a hole cut near the ogive area. In one side goes a dial guage and the other side has a threaded section in which a nylon tipped shaft lays against the ogive. On the opposite end of the threaded shaft is a handle for adjustment purposes. You push the round into the chamber, hold it down and adjust the dial guage in or out till the shaft of the guage goes in approximately .100. You then spin the round and get the total runnout. You pick the high side of the runnout and then use the asjustment knob to push the bullet and eliminate any and all runnout. Works fantastic and eliminates all flyers

 

[ArmyCW]

I'm going to try a new set of Hornady Custom Grade New Dimension
dies. Better resize die, and from my understanding of coments from other much better bullet seating die to help reduce most of runnout.
Maybe a few bad brass cases too.

Kenny

 

[Ol` Joe]

I'm going to try a new set of Hornady Custom Grade New Dimension
dies. Better resize die, and from my understanding of coments from other much better bullet seating die to help reduce most of runnout.
Maybe a few bad brass cases too.

Kenny

The Hornady dies work well in my limited experiance. The Lee collet neck sizers seem to give the best result for me, but others may not agree. The major problem with getting runout under control is case wall uniformity. You can`t get good runout with brass that is 0.004" thicker on one side then the other. This takes neck turning and a whole new set of head aches.
BTW I have the RCBS tool and do at times use it when setting up a sizer. I seem to find more variation in the sizeing process then bullet seating. YMMV