Should the forcing cones be opened up on older doubles? I have heard that the old shot shells with the rolled crimp over a wad procduced a shorter over all hull than the newer pastic shot shells with the star crimp and shot cups.
I have the 12 gauge reamer to do so, and have opened up a few, but have heard conflicting stories as to whether it is required or not.
Supposedly it is suppose to reduce the pressure and help the shot pattern. What I heard was the newer shells with the star crimp, has the crimp opening partially into the forcing cone on some older shotguns.