Probably a politically-correct term for a sniper rifle. THe idea was to have a sniper-grade rifle with quick repeatability of shots to engage multiple targets (like the Bosnian snipers in the apartment complexes). Interdiction of targets, per se.
ArmsTech in Arizona was the contractor, but McMillan no longer offers their custom A2 stock configured for the BAR action. I was all ready to build my own variant, using a beat up older .300 Win Mag BAR, but may have to wait until I find a suitable stock.