Originally Posted by
bigcountry
Yep, that shell holder is generally the culprit. Briman on here took his spring out of the ram and lets his shell holder float. Worked well for me too. I can't say I can achieve 90% less than .002, but I do something simular I bounce my bullet/brass while seating. I will raise the ram right to where it wants to push then drop back down, it will center my brass. I get do get consistent less than 0.003 and .004" this way.
Sounds like you have taken it to a whole new level. I don't blame ya for comp shooting. Everything is everything there.
I let mine float as well BC, but that still creates a problem. Get down below your press and watch that brass go up in the die. Just before it goes in, you can see it tip ever so slightly. Same thing coming out. That rubber seal holds onto you brass a little and you can see that brass tip again as it falls back into the shell holder when you lower the ram.
Get that bullet going in the brass straight at the earliest stage. Spinning half way through the seating process has given me mixed results.