Looks like they went 20" with a 4.5-14 Leupold.
http://www.thefirearmblog.com/blog/2011/...marksman-rifle/
http://www.thefirearmblog.com/blog/2011/...marksman-rifle/
Designated Marksman Weapon (DMW) 7.62mm Rifle
The 7.62mm DMW provides enhanced target detection, recognition, identification and acquisition at section and patrol level. With a trained operator, the DMW will provide the capacity for lethal, precise and discriminate fire, neutralising enemy combatants and suppressing them at long ranges. The DMW is a magazine fed, gas operated, air cooled weapon with a rotating bolt locking action. It is capable of semi–automatic and automatic fire. The primary sight is a 4.5 -15x Leopold Mark 4 telescopic sight. For close quarter battle a set of Dueck Defense rapid transition sights are issued.
I believe the BUIS and muzzle break are from SureFire.
SureFire Rapid Transition Sights | Iron Sights
SureFire SFMB-762-5/8-24 Muzzle Brake / Suppressor Adapter