I have a marlin 336 sn indicates 2002 manufacture. The measurements of slug are shown in pictures attached.
Lands 0.3025
grooves 0.307
Bullets cast from rd 311-165 drop at 0.3125
when chambered it takes a fair amount of force to close lever, but bullets are not pulled from case on extracting dummy rounds.
last pictures show rounds as extracted.
In the general opinion should I size back to .310? Or will I be fine to run these as cast?
I have thought about shortening Cartridge length by trimming cases, what length have any of you that have shortened cases trimmed to? what overall length have you decided to use?
I guess my general impression is that the marlin bbls are oversized all the way around (land and groove), possibly just a brand new tool when rifling this one?