The title may appear contradictory. My Cetme's markings further states: Century Arms Inc., Georgia, VT, Made in USA. Serial Nr. C334xx. I've read somewhere that some barrels were produced in this country. I assume most were imported from original manufactures in Spain or Germany. My question is: Is there any way for me to determine whether the barrel on my rifle is .308 or 7.62x51 NATO. The reason I ask is that the NATO shoulder of the cartridge may be slightly longer than the .308. If so, chambering a NATO 7.62x51 round in a .308 chambered barrel might be like craming it into a "short" chamber. Yet, all seem to say to fire the NATO round in this rifle. Where is my reasoning going wrong, or is it???