runout driving me nuts
I have struggled lately with bullet runout. I have followed all the suggestions. I rotate the shell about 5 times while seating a bullet. I deprime separately and raise my expander ball to the top when FL sizing. This produces 1mil or less brass neck runout. Which I can deal with. I square up my sizing and seating dies by putting pressure on them with my piston before locking my locknut. I then buy this 70 dollar Redding seating die. I think I have better luck with my RCBS seating die. Even though this redding will set you COL dead nuts on. Pretty cool.
But while loading 20 190gr matchkings last night, 7 out of 20 has runout around 4 mil. The other 13 is 2mil or less. I not even sure it even matters much. I just want nice little 5 shot groups at 200 yards. I get this nice 3 bullet cluster about .5" then 2" low at 200 yards. I get this ugly flyer. I know I am really picking pepper out of ant $hit, but I want to compete one day.
Loaded 20 more Triple X last night. About the same story 10 out of 20 bad runout. Seems its critical during the initial seating. Not sure what else to try. Maybe my shell holder? It does seem to float a little on the piston. Maybe try RCBS competition die? Maybe that 1.5 mil brass neck runout causes the bullet to insert wrong sometimes making 5 to 7 mil runout on bullet near the ogive. I mean its hard to correct for 1.5 mil brass runout.