I have a VERY basic U.S. Army M-14 wearing polymer stocks. I have had accuracy issues as of late. With the sights set for 100 meters, firing at a paper target at 100 meters from the bench, I am 12-14 inches high. This seems a bit extreme to me. The first time it happened I thought I was crazy and immediately picked up my Garand, all eight in the bull ring. The stock was on a bit tight so we loosened it up a bit, thinking that there was pressure on the barrel. Shot it again today, still a foot high. Shot the Garand again to ensure that it was not user error and the Garand was right on. I'm not an expert on the inner workings of the M-14 so at this point I will take any and all suggestions. Thanks.