Hey everyone..I'm new to the long range hunting ..I posted some pics of my tikka 300 wsm awhile back shooting very well. Recently its been shooting awesome for me anyways... at 400 yds I was usually within 3.25 Inch group. The only cleaning.of the barrel I do is with a bore snake...the other night I loaded.some virgin brass I didn't expect great groups because its not.fire formed......but anyways I was inspecting my gun and saw some copper in the barrel. .so I ran hopped #9 solvent and a copper brush...followed by 10 dry patches..but when I went to shoot my next few rounds the gun has started shooting the worst it ever has and I'm wondering if it's because the barrel is not as dirty as it once was or because the Virgin brass I just wanted to see if any of you guys have had a terrible accuracy with a clean Barrel...my groups at 400 yards were about 9 inches! What did I do wrong???