I fit a new Kart NM 45 barrel to my Clark Heavy Longslide I found a way to verify to make sure the primer is centered I know they make a tool but I'm a garage gunsmith.
I took a new empty case drilled out the primer pockets to accept a 3/32 punch and it fit in the firing pin hole very closely. I left it in there thru the whole lug cutting process and it came out perfectly centered with a .043 thou lock up I think is my best barrel fit job yet it's nice and snug have to give it the bump on the back end anxious to test ! I also used the Brownell's lug cutter kit don't get the impression this is all I used to hold the barrel locked up during the cutting process.!
I took a new empty case drilled out the primer pockets to accept a 3/32 punch and it fit in the firing pin hole very closely. I left it in there thru the whole lug cutting process and it came out perfectly centered with a .043 thou lock up I think is my best barrel fit job yet it's nice and snug have to give it the bump on the back end anxious to test ! I also used the Brownell's lug cutter kit don't get the impression this is all I used to hold the barrel locked up during the cutting process.!