Thank you for information. I may be long on the brass yet. Have not been able to fireform brass to try and measure to see if i can find a proper case length. Going to show the chamber cast with brass. As you should be able to see no true cutoff for Cart. unless this has a end taper. My case is already smaller at the neck then the base and have trimmed brass to where it is a good push to get rim inserted. bore has strong rifling and measures about 12.8MM[img]https://imgur.com/sCuRenl[/img]

William