I just picked up a brand new Springfield M1A Loaded and after getting it home I found out the headspace is 1.637". The reason for my concern is I have a bunch of .308 Prvi Partizan and I'm not sure it is safe for my rifle. The No-Go gauge for .308 Win. is 1.6340" and the Field gauge is 1.6380", so if I understand correctly using .308 in my gun would be pushing it? Please help me understand. Thank you for your patience.