My best friend and oldest son were both M-60 gunners. My son was using a 1960 mfg weapon in Iraq, 44 years old and still would do anything he ask it to! There is nothing wrong with that gun! If it ain't broke: Don't fix it. When the nature of war changes, then we will need a new primary weapon. For example: 1) By the end of the Civil War, muzzle loaders were no longer feasible. 2) By the end of WWI, Bolt action and single shot rifles needed replaced. 3) By the end of WWII & Korea, semi auto rifles were questionable at best.
The environment of the Middle East/SW Asia is different, but is long range warfare different? or House to house?
I have heard arm chair warriors (of which I am one!) complain that our current enemy just stays out of rifle range. That hasn't changes from General Custer's day or General Washington's or Ogg the cave man's day. A longer range primary weapon won't change that. In fact deer did that to my family in Ohio and Wyoming!
When we went from the M-14 to the M-16, it took how many years and how many lives to get it straightened out? (6 or 7 years and as many as 10,000 according to my Vietnam Vet Marine friends!)
Are the current rifles and SAW type weapons reliable? Yes! Are they perfect for every situation? No! Are they good enough to work for where we go to defend our country? I think, Yes! Do we need a new system for the foreseeable future? NOT YET! The only place our systems haven't been is Outer Space. (I heard a rumor in the early 80's the Russians had a AK system for Vacuum)
Ivan