It is seldom found being used by players in Free Roam, due to it being unlocked at Level 49 (the penultimate level of experience) and the fact that players entering Legend Mode lose access to the weapon until returning to level 49.
The Mauser Pistol is a fully automatic gun, meaning that if the fire button is held down, the gun will shoot continuously until the magazine empties, making it the only automatic weapon that is not mounted. However, the rate of fire is drastically reduced in Multiplayer.
The player can fire the Mauser Pistol more quickly in multiplayer by firing it as a semi automatic gun, and rapidly tapping the fire button.
Having the largest magazine capacity of any pistol makes the Mauser an excellent choice for Dead-Eye Targeting, as well as dueling.
Although it is not the most powerful handgun available, the large magazine and blistering rate of fire enables the user to "double-tap" multiple targets; two torso hits from a Mauser will kill any NPC, and all but the biggest animals.
The player can get the Mauser pistol and all other rare weapons in Blackwater at the beginning of the game by getting arrested in a certain area north of MacFarlane's Ranch and being transported to Blackwater given you have the funds and are able to make the jump back across Dixon's.
The Mauser Pistol, when used with Dead-Eye, has enough shots for the player to put two or more bullets into each respective body part (2 head, 2 chest, 2 left arm, 2 right arm, 2 left leg, 2 right leg, 3 extra shots).
Due to its large magazine (holding 15 rounds) and medium power, it is very effective on horseback. It is also very useful when used in Dead-Eye, allowing the player to mark and execute many enemies. The large magazine also makes this gun very effective with some of the upper levels of the Sharpshooter ChallengesAmbient Challenge.
It is a very effective weapon against any other player in any game mode, due to its somewhat large magazine size and high fire rate.
The weapon will kill any NPC with one shot to the head or two to the torso, making it very useful against Lawmen, bandits, and other NPCs.