My one Redding die set has a deprimer/sizing button that is badly of centre. When I asked I was told they were all like that (and indeed they were) and that it made no difference.

Does it make no difference? It seemed an awfull piece of engineering to me - should you leave it loose and not lock it up with the lock nut? Why do supposedly 'crappy Lee' dies have a centred sizing button?

Supposedly, when left loose, they will self center in the neck w/o distorting the unsuported neck & shoulder when pulling the brass back over the expander ball upon removal of the case. Males sense if you think about it. With regerd to the LEE dies (at least the set I have) The FL sizer is rigid but the neck only sizer is floating. You should be able to move the assembly back and forth with your finger on the decapping pin.

PS.. The Lee stuff isn't all that crappy, just inexpensive.

This is the exact reason I would hate to reload without my rcbs casemaster to check runnout. I have found the by looking at the spindle they can fool you badly. Some look offcenter but yet, somehow they make good runnout. Others that look centered don't. I've found that by making small 1/16-
1/8 turns you can usually find a sweet spot that makes straight ammo. Once I get that I never reset the spindle or the lockring. To change headspace for a different gun I use shims under the die to change the headspace by a few thousands of an inch.

I could write a book on this subject. In my experience the worst thing you can do to a sized case is drag an expander plug back through the neck. Run a case into a die without the expander and measure runout then do it again with the plug; yuck is all I can say. I have tried the floating carbide buttons, the standard ones and the high mounted buttons all with equally lousy +inconsistent results. The best so far are the sizing bushings, provided that no one sizing reduces the diameter more than .003-.004". With this process I can hold run out to .002 or less WITH a straight-line seater. Right now I am trying to find a bushing sizer and s.l. seater for my .300H&H. It is the worst cartridge for run out that I have encountered, and my fired cases will run .0015 or less.
Note: I have found that measuring run out, like patterning a shotgun, can become an obsession.
C.G.B.

CGB,

Sinclair lists a Wilson in-line seater for the 300H&H.

http://www.sinclairintl.com

Also, there's an advertiser in Precision Shooting that will convert your standard sizing die to accept bushings. Don't have the name right now but will look it up for you.

Thanks for the info on the Wilson dies. Forester will do it as a special order for 100$. Neil Jones also makes custom sets to fit your fired cases. I think these are about 200$ a set. I will have to check out the Wilson dies, their prices are very reasonable.
C.G.B.