They're R0727 carbines with M16A2 stocks and laced on cheek pads.
Handguards are carbine length FF tubes (possibly Bushmaster/Quality Parts V-Match, but simple aluminum FF tubes were not uncommon at the time, and it could also be a cut down rifle length tube, etc.).
Scopes are most likely either Leupold Vari X 1-4s or Microdot 1.25-4x, but could also be a couple of other commercial offerings that were also used around that time, and most likely with SIMRAD mounts.
At least one is equipped with an Israeli AIM-1 IR laser as well.
Another photograph of a similar Navy rifle from Somalia that helps to fill in some additional details, though this one has been a little bit more highly modified with a shaved front sight base and carry handle removed with a section of Weaver rail to allow lower mounting of the scope:
Note the A2 stock, heavier R0727 barrel, and Leupold "gold ring" on the objective end of the scope, as well as the AIM-1, FF tube, and SIMRAD mount.
The Ranger "DMR" was significantly more simple than these weapons, it was a stock R0727 with a Harris BRM 9-13 mounted to the plastic handguards, a [mostly likely] 100MPH tape and sleeping mat cheekrest, and a Leupold M3A Ultra [mostly likely] robbed from an M24.
~Augee