Good luck trying to find one in .308,Remington only makes the 7400 carbine(18.5" bbl) semi in 30.06 and the 7600 carbine (18.5" bbl) pump in 30.06.I have the 7600 carbine pump in 30.06 and it's a sweet woods/brush gun.It's been that way for several years,the 30.06 is not available in carbine.You can get a regular 7600 or 7400 with the standard 22' bbl and that too is also a great gun.Remington makes the 742 or 7400 in a .308 carbine in a semi. ( Which I own).
Theoretically the .308 is slightly more accurate and the 30-06 has slightly more knock down power. Unless you are a world cl [no swearing please] high power shooter I doubt you will notice the difference in accuracy. I have owned both and see no difference at my level of shooting skill. The supposed difference in knock down power, if there is really one, you will never notice on a deer size animal.The .308 is very similar to the .06 and .270.