I "use" a rifle for deer hunting, National Match Course and silhouette shooting. IMHO, the one best rifle to cover these bases is the M1A. It is an effective, if heavy, deer rifle, it is great for HP target shooting and can be scoped for silhouette. The M1A is also a fine fighting rifle, should the need arise.
An AR would be good for the NMC and for fighting but it is light for deer hunting and won't knock down the steel silhouettes.
A good bolt gun in .30-06 or .308 etc. would cover the hunting, target shooting (with clip slots) and silhouette but would not be the best choice in a fighter.
I would hate to be limited to one rifle for everything, but if that were to happen, I would pick an M1A.
YMMV
Drue