The HVM Heavy Machine Gun Sentry is the cheapest, though not the most cost-effective, turret. Unfortunately, the limitation of 2 turrets (until you get level 5 mastery for turrets, which extends the limit to 3) makes it ineffective in later levels (50+), due to the far lower damage or utility output compared to other turrets, and the far stronger zombies. It is, however, good for covering you while you reload, killing medium swarms while you fight a boss, or shooting Shielders from behind.
This HVM turret is highly effective against weaker and medium sized swarms of zombies, and even can be used to take out Bloaters or a chunk of a boss's health. Overall, this turret is a great weapon and can mow down hordes of zombies due to its pierce and fully automatic stopping power.
As an automatic turret, HVM Heavy MG Sentry's appearance is quite modern, being a stationary heavy machine gun with a rectangular platform. It has quite big muzzle brake (possibly due to its high caliber as for a turret). It feeds with ammo belt on the right side of the turret (similar to Z-5, which is a LMG though).
The overall design of the turret is very similar to the Sabre turret in Borderlands 2, both having a camo paint on them, being belt felt, and having a rectangular base.
The description might be unfinished, as "calibre" is misspelled (spelled caliber), and that the design of the turret features rounds that may be not caseless, even though the description says "MEP caseless rounds".
The BLACK version's Damage is unknown due to it not being in the game, although the BLACK turrets are a questionable topic altogether
In game when picked up as loot, the turret is called "HVM Turret" when picked up.