Case Expansion (Width, Not Length)

[QEU]

I have two Remingtons, 243 Mountain and 308 LVSF, that I reload for. In both rifles, the width of the case expanded after the first fire. There are no signs of pressure. I load with minimum charge only, never max. I noticed this because I started using the Wilson case trimmer that has been sitting in the garage for over a year. The trimmer have a case holder that holds the brass in place to be trimmed. New brass would fit into the case holder. Once fired brass would not fit. The other non-Remington rifles did not have this issue. Does this mean I have oversized chamber for both Remingtons?

Has anyone dealt with Remington's customer service on this issue? What can I expect from this. My only gripe is I can't trim using the Wilson case trimmer.

[ar15barrels]

All guns do this to some extent.

Wilson sells different case holders for new brass and for fired brass for this very reason.

[QEU]

AR15,
I was not aware that Wilson provided fired brass case holder. Thx.