I bought an X-die from RCBS a couple years ago, the thought of not having to case trim sounded too good to be true. I've set up the die per the instructions and checked it 2-3 times. The problem I'm having is the shoulder seems to compress and bulge developing a rounded-shape when I use the die. Being quite concerned about accuracy I went back to my standard die and did all my loading for the season last night.

My question is how do you like your X-die and does it work perfectly for you? Or are you seeing the same issue as well? I'm not totally sure where the cartridge sits in the chamber of my rifle and whether a round shoulder/neck would affect accuracy comparred to a straight shoulder.

Re read the instructions and follow them to the letter.
I have an X-Die in 220 Swift and have not trimmed the brass after the initial trimming.
Some may try to tell you that the necks will thicken with use but offer no proof! The new Midway flier tells in the X-Diew description that the die will not cause neck thickening.

I checked the directs many times. It's not really thickening the neck, more like bulging it out from straight to a round appearance. Either way it just doesn't look right so I've stopped using it.

Never tried them but I guarantee you that if you call the 800 number at RCBS they can help you. Their customer service and technical assistance is second to none.

Good idea, I think I will give them a call. Thanks!