30/06 rifle also have chamber and throat dimensions which are all over the map, but again, as long as the chamber and throat are straight and concentric, all will perform well. The most accurate 30/06 hunting rifle I ever owned had a very long tapered throat. It is obvious that ammunition plays a major part and I mentioned the use of issued ammo only to illustrate that the ammo could, in fact, negate any rifle building efforts. With good ammunition, one could see some improvements but they were surprisingly minor. I feel that neck diameter, for instance, is pretty well meaningless. The real bottom line, at least for this discussion is: 308's will shooter better than 30/06's, if all else is equal. GD
