I just got my Graf and Sons catalog and found a listing for RCBS X dies. The claim is that these dies will not stretch the casings thereby eliminating the need to trim beyond the first trim to bring all the brass down to a uniform size. Any experience with these dies of this concept?

They sure do work, and I have been going over to them more and more as I use them....sure saves those dreaded hours at the trimmer, especially with the varmint calibers wherein one shoots a lot of ammo....You may have to trim after about 7 or 8 firings but the brass is pretty well junk by then.

I like them quite a bit. Saves you from trimming, chamfering & deburring and my cases load just fine. I find case prep to be pretty tedious but that's just me.

Has anyone got anything to say about concentricity with these dies. Part of the principle is that they use a mandrel--to me that could add (or deduct) from runnout problems associated with the sizing ball at the end of the stem in a normal die.

I just back 2 sizing die I sent back because of of a rough neck.Left a mark on the neck when I resized a case.called them up ,they said send them back,They were back in 12 day turn around N/C
I am happy with RCBS.I use 14 calibers of theres.
2 rock chucker press .Hard to beat.

If you buy a f/l die, there really is no reason NOT to buy the X-die. They do work as advertised, but if you back off the top adjustment, they work exactly like a regular f/l die, as well.

A two/fer, so to speak. HTH, Dutch.