An Elephant Gun is a large caliber firearm intended for hunting, as the name implies, big game like elephants or rhinoceroses. Early elephant guns were large bore black powder guns that fired solid lead balls, but modern elephant guns fire high caliber cartridges like the .700 Nitro Express or .600 Overkill rounds. Generally, these rifles are either single-shot, double barrel, or bolt-action guns, with the intent being that the round would have enough stopping power to kill charging game with only a few shots.
A triple-barreled Merkel Drilling elephant gun firing .700 Nitro Express is featured in Battlefield Hardline as the Mammoth Gun.
The Mammoth Gun is an all class rifle introduced in the Battlefield Hardline: Betrayal expansion. The Mammoth is a triple-barreled, break-action rifle that functions similarly to the Double-Barrel Shotgun, but fires the powerful .700 Nitro Express round, allowing it to kill in a single shot out to 30 meters. However, the rifle has very high recoil and only holds 3 shots per magazine. Along with this, it has a long reload time, so the player should be careful to avoid firing all rounds too quickly and being stuck reloading. The Mammoth cannot equip any attachments but can still use metallic paints.
The "Big Game Hunter" assignment may only be completed on a ranked match of Chinatown on Conquest Large. The map features six small mammoth head statues scattered through out the map. In order to complete the assignment, players must first collect the statues. Afterwards there is a button hidden under a desk near the main alleyway that unlocks a secret room found behind a freezer. Inside the room is a trophy shelf with the Mammoth Gun featured in a locked gun case above. This case may be unlocked once all six statues are collected. Afterwards, the player must pick up the Mammoth Gun in order to complete the "Big Game Hunter" assignment and unlock the weapon permanently.
When collecting a statue, a distinct animal sound will ring. Statues may only be collected once per round and do not carry over to subsequent matches, meaning that every statue will need to be recollected when a new match begins. Statues are collectively obtained, meaning that numerous statues may be collected by different players and it will still count toward unlocking the gun case. This also means that a player does not need to collect a single statue in order to unlock the gun case and pick up the gun.
Once the case is unlocked and the weapon collected, it will be signaled to all players with the same distinctive animal sound heard when collecting statues. It can only be picked up once every round by a single player and does not respawn, meaning that players need to race to the room where the weapon is held before it is taken by another. This results in heavy firefights centered around the area as well as the very likely possibility that players may be "betrayed" by teammates when attempting to pick it up.