308win, Any case that you have that is headstamped LC + a two digit date code is milspec.
Max loads depend on quite a few things including the case just because a manual says the max load for 308 win using x powder, y bullet etc. is 48.5 grains doesn't mean that it will be a max load in your rifle.
Milspec cases are in general, thicker than commercial cases. This gives the milspec case less internal volume than it's commercial counterpart. Less powder in the milspec case will yield the same pressure as more powder in the commercial case so you will not give up any velocity using the LC cases that you have.
If you have a Hogdons reloading manual around they have a load for 308 and one for 308 match. The match loads were worked up using GI brass. You can make a good comparison there.
HTH