hello its been a spell since ive been on here.last time i was waiting on my 280 to get finnished.its now done and ive been playing .short rundown its a 26 inch bartlien barrl on a browning xbolt chassis it was put together by someone who knows what is what any how i wanted to shoot 168 bergers my coal is right at4.00 using reloader 19 i started soft and at 51 great all touching aol was at 3.900 did not chrono but book said around 2500 as i went up to gain some vel she started to spread and at 53.5 stringing my bud said i might need to jump them some any body out there with simaler things with the bergers?? thanks