I have a winchester 308 model 100 semi auto and am haveing trouble with it .It fires the first shell ejects it but the second jams on an angle going into the barrel, I have tried all different shells and they all do the same thing except for the old millitary hardballs it will fire them all day and not jam on me. I have had it to 2 gunsmiths and niether can find the problem,would anyone have any suggestions that I can get checked out any help would be appreciated as this is a really nice gun thanks