BEEN THERE DONE THAT.
THE ONLY 2 GUNS THAT SELF-LOAD AND COMPETE WITH MODERN SNIPER WEAPONS ARE:
AR-10/SR-25
TROY SOPMOD M-14
I built a M1A once (SA supermatch modded and worth $3800) and it still shot worse than a Ar-10 T (about 1-1.5MOA) and it (with Bi-pod sling, loaded mag and scope) weighed in at 22.5lbs!!!!!! The $1600 Ar-10 T weighs about 10.5lbs. (or about 15lbs with a bi-pod, sling, and scope) The Troy M-14 weighs about 8.5lbs (probably 13 with optics and bi-pod) and from what I here it will give a M24 or M40A3 a run for its money.
The M1A bush rifle with RAS is a good way to give a soldier .308 power and range as long as extreme precision is not needed. expect 1.75-3MOA with anything less than $3500-$5000
I know there are units in the military that still use the M-14 (mostly highly modified examples ) all I can say is better them than me. The rifle has serious maintenance issues (lots of parts to cleaned lubricated and protected from corrosion, some parts that need to be greased (attracting dirt and sand) bedding that is easilly damaged by removing the action from the stock for routine maintenance, Tools are needed for cleaning the gas system, Scope mounting issues, etc.
The Ar-10/Sr-25 is a much better option for the field and my bet is that troubles with procurement, and procurement funds are all that are keeping units from fielding them.