OK so I have a Savage .308 tactical rifle and it has been shooting like a dream or as close to a dream as can be expected for an out-of-the-box rifle. Sub MOA accuracy, reliably on steel at over 1100 yrds...etc... Well I have a fair amount of shooting done with it and I decided to give it a good cleaning. I always clean it but yesterday I decided to get some Barnes CR-10 copper fouling remover. I spent a fair amount of time getting all the copper out. Then I took it out to the range today and it shot like crap for the first four or five rounds. I understand the importance of cleaning but maybe someone could answer why I should spend all that time taking all the copper out of the barrel only to have to shoot four or five rounds to get the layer of copper back in to shoot good.