Gunday Brunch #28: The best US Service Rifle that isn't an M16 variant

The absolute best service rifle the US military has ever fielded is the M16 family of weapons. This is a fact that really isn't debatable unless you're a contrarian, so today the boys are trying to figure out what rifle is the "best of the rest." Is the M14 the second best service rifle? Or perhaps the M1 Garand?