I had no idea this site existed.  I duckduckgo'd primer size for 10mm and this site popped up so here I am.

G29, Tangfolio steel, and Witness polymer (that won't feed). 

Primarily I'm here to try to diagnose the Witness polymer.  I'm hoping some of you have solved the feed issue as I very much like the pistol feel and weight.  I think it would make a good ccw. 

Glad my search engine found the site.