08-05-2012, 11:38 PM
I went through the same problems a few years ago when I started with the Grendel. I was resizing IMI brass, with Redding dies and shellholder, and having problems. Eventually I took some w/d sandpaper of varying grits and lapped a little off the top surface of my shell holder so I could bump the shoulder back a bit more and it solved the problem. I did not do any measurements before and after but just did trial and error until I could get the bolt to reliably go into battery with sized cases.