SAW was...
1. not accurate enough
(It was a belt fed light machine gun, not a sniper rifle. It is meant to control an area and to lay down a base of fire to support maneuver)
2. location easily detected by the enemy
(Ok, you have found a machine gun well emplaced and pouring fire on you...your move)
3. very high consumption of ammo
(That also means it sends a LOT of ammo in the right direction. That’s a feature and a blessing to a grunt needing fire support, not an problem. That same wasting ammo complaint saddled the 7th Cavalry with single shot Springfields when the Cheyenne and Sioux had Henry’s and Winchester 66’s)
Just for fun... an inaccurate M-249 at work against an RPG shooter. An oldie but a goodie.
https://www.liveleak.com/view?i=3ce_1374246544
Oh, the SAW was so much fun to shoot! Only got to do that once at Fort McCoy during weapons familiarization. Then on the same range I got re-acquainted with an old friend, Ma Deuce. Fired five rounds, paused & when the dust settled they were still on the way 800 yards down range.
The SAW is a scaled-down M-60, am I right? I fired it from the hip like in the movies.
Did I mention I was 60 at the time? Old warrant officer here.