A Coaxial HMG is a Heavy Machine Gun mounted coaxially to a tank's main cannon. Most main battle tanks come with a 7.62mm GPMG built into the turret, sighted and fired by the same gunner who operates the cannon. A coaxial weapon allows engagement of exposed infantry and urban combat without the collateral damage of firing the main gun. Most examples of a large coaxial are modifications rather than part of the original design. The M1A2 Abrams "TUSK" (Tank Urban Survival Kit) can add a M2 12.7mm machine gun over the 120mm cannon.
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17700 MBT score
• Secondary weapon for tank operator
Main Battle Tank (Driver)
|Battlefield 3 Tank Guide - Coaxial HMG(05:28)|
The Coaxial HMG is a vehicle specialization in Battlefield 3. When used, the driver gets a secondary weapon for use against enemy personnel and light vehicles. Compared to the Coaxial LMG, it benefits from a much higher damage per individual bullet, at a max of 50 trailing down to 34, and a higher accuracy, at the cost of firing at a significantly slower rate of fire. Unlike the Coaxial LMG, the HMG does not overheat, allowing for continuous fire.
The HMG can engage infantry at any range, but is the single most effective long-range anti-infantry tank weapon, with the first 3 shots retaining perfect accuracy. It deals 34% damage per shot, even at maximum range, so it will kill in 3 shots in normal mode and only 2 in Hardcore mode. The HMG also has the fastest bullet velocity in the game, clocking in at 750 m/s. This makes the HMG great at taking out long ranged targets. It can also engage light vehicles, but the Canister Shell has a higher damage per shot. In Hardcore, it can one hit kill at any range if it hits the head, or a chest shot and higher at close range.
Unlike the LMG, the HMG can damage lightly-armored vehicles, including jets and helicopters. Its high velocity, however, is offset by its low fire rate in anti-air combat, as well as the tank turret's slow and vertically-limited traversal. As the Canister Shell does not require maintaining aim, is more forgiving, and deals excellent damage, it is generally more effective on air targets within close- to medium-range.
The Coaxial HMG is larger than the LMG, so it is mounted above the main cannon rather than through the traditional gun port. You can see it easily in first-person view. Interestingly, on the T-90, it can be seen attached the the main cannon barrel via metal band, but when the cannon is recoiling after a shot, it does not move with the barrel. It also does not seem to have an ammunition source.
After the 1.04 Patch the fire rate of the HMG is much faster than before, while still avoiding overheating. The Armored Kill patch gave it greatly increased accuracy.