It appears in the mission Belly of the Beast where the player will have to destroy one, in the form of a boss battle. It has a high rate of fire and a shield in front of it, which is nearly impenetrable. It can destroy cover rather quickly, and can kill the player in just a few rounds.
To defeat the DShK, the player must shoot in the general vicinity of the gun emplacement, suppressing it so the players squad mate can throw Red Phosphorus onto it, marking it for an air strike.
Defeating the DShK under a certain time rewards the player with an achievement/trophy.
The DShK is an emplacement on some Medal of Honor maps, namely the Combat Mission maps. It still appears with a shield, and its movement is heavily restricted. However, it has unlimited ammo, high rate of fire, good accuracy, and high damage.
It is not often used by players, as there are often many enemy snipers that can easily take out the gunner in a single headshot.