I'm thinking "too many mods". Sure the M14 with a shortened barrel is sort of OK and maybe a fiberglass stock, but I prefer the good old M-14 without the full auto switch (Army's big mistake, fortunately caught quickly) The .308 is a good caliber especially with hollow-points. OTOH, maybe an M14 action modified for the Blackout round and with a supressor, but that's already available out there. I like the Blackout with sub-sonic hollowpoint rounds, especially if the hollowpoints are filled with a fast-acting nerve agent. But to really reach out there and touch someone, I still prefer the M1903A1 Star-barrel Springfield in .30 caliber and a modern optical sight system. It only takes a second to throw the bolt and chamber the next round and when you are killing a target at about 300 to 500 meters, the target won't get any closer - assuming you are a very experienced expert marksperson as I am. Of course, having your spotter close and armed with a rapid fire auto weapon helps in case they sneak up on you or something.