I have a 6.5x55 on a trued remington 700 with 27" lilja barrel. It is in a medalist stock that I skim bedded. It has a zeiss conquest 6.5x20. I have about 550 rounds down the tube. It has been a solid 0.5" gun but the last few times I shot the gun it shot about 1" at 100. Today I couldn't keep it on a 7" plate at 550 yds. The brass has 11 firings but the primer pockets are not loose and no split necks. My load is 44.5gr h4350 berger 140 vlds 3.120 which is 0.015 into the lands. Anyone have any ideas on the problem? New brass? I checked the distance to lands and hasn't changed. Thanks in advance.