Though I've killed a few deer with a .22-250, the lightest caliber I recommend for deer in Maine is the .243 Win, using 100 grain bullets.
The .30-06 is the most common caliber used here, and though we're one of the most heavily-wooded states, the most popular rifle here is a scope-sighted bolt-action. At one time the most popular was a .30-30, Winchester 94, but those days are gone. The 30-06, .270 Win, .308, 7mm-08, and .280 Rem, historically get-er-done very well up here.
Newer short-magnum cartridges, especially the .270, 7mm, and .300 are also probably fine Maine deer cartridges. The 7mm rem and .300 Win Mag are also popular. Magnums are generally unnecessary for the deer hunter who can hit a paper plate at 100 yards...every time. Come to think of it, if they can't hit the plate, they probably shouldn't be shooting a magnum either. Practice, practice, practice.
Picher
The .30-06 is the most common caliber used here, and though we're one of the most heavily-wooded states, the most popular rifle here is a scope-sighted bolt-action. At one time the most popular was a .30-30, Winchester 94, but those days are gone. The 30-06, .270 Win, .308, 7mm-08, and .280 Rem, historically get-er-done very well up here.
Newer short-magnum cartridges, especially the .270, 7mm, and .300 are also probably fine Maine deer cartridges. The 7mm rem and .300 Win Mag are also popular. Magnums are generally unnecessary for the deer hunter who can hit a paper plate at 100 yards...every time. Come to think of it, if they can't hit the plate, they probably shouldn't be shooting a magnum either. Practice, practice, practice.
Picher