RCBS X-Die

[Jafar]

Anyone used them? I was helping a buddy load earlier this evening with one. It seems like it works in theory but I've yet to see how it effects performance.

[mapper]

I haven't used them, as I use redding or rcbs dies set up to bump the shoulder back 0.002 from fired dimensions, and trim each time as it is easy and consistient for me to do so.( no rcbs-x, or redding bushing dies, just standard ones)
But.... I did find this.

http://thefiringline.com/forums/archive/index.php?t-22078.html

[Jafar]

It seems the most satisfied users are reloaders of .223/5.56. As far as the M1A group, I was taught never to reload brass that had been fired through one. And I'm as detailed as a Chinese mathematician wearing a tight pair of skivvies when it comes to reloading, so I never had an issue with trimming over and over again. I just accept it as a part of the process.

It seems that if the case wants to stretch, and we stop it with the mandrel, the stress will develop eventually in the shoulder anyway - forming a bulge or giving signs of overpressure.

[mapper]

Like you,
I believe that brass has to flow somewhere.
I just size my brass minimally to fit the chambers.
And set trim to length max less .003~.005 as I do it each time.

Not a big deal to me to lube,decap with universal decapper, turn turret, size, put in power trimmer, put on case prep center for chamfer/deburr, neck brushing, crimp removal, and primer pocket cleaning,
Takes about 20 seconds or less per case.
Done consistent every time.