Thanks, guys, for your replies.

Rule3 asked:

Are both the pictured empty brass from the same gun??

I doubt it, but frankly I don't know. A couple months ago, when I started to seriously consider reloading, I just began to save all my fired brass. I did not separate the brass according to which of my three 9 mm's had fired the brass. Of course, now I will begin to watch that.

I thought maybe someone would know about the chamber support situation as it pertains to my particular pistols. The sig P226 has good support I think I read. i don't know about my M&P 9C or my Kahr CM9.