the marines have a short action 700 308. google m40 and m24. the army uses a long action.army could change to a 30-06 real easy. not going to . orginally they thought of one shot and evade. not now. the contract has already been made for a semi-auto tricked out ar-10. it has the ability to engage multiple targets quickly. the 30-06 is balistically superior to the 308. my opinion is that F-class competiton is a fair way of comparing the relitve merits of a certain caliber. 6.5-284 win a lot. the .308 does not only in its class. the 308 is in a different "class" than the 30-06.