The Magnum is slow and somewhat cumbersome, but when you hit an enemy, they know they've been hit. In fact, if there's another unprotected enemy behind them, they get hit too. It's a twofer.
The Magnum is the most powerful handgun in the game, having one of the highest damage per shot statistics, second only to the Sawed-Off Shotgun. The Magnum contains eight shots in the cylinder, meaning that it has more ammo than the revolver, but less than the 9mm . The Magnum's rate of fire is similar to the revolver's, giving it a higher damage per second output. This makes the weapon a very appetizing choice for the player's right slot weapon, especially because it can take out multiple enemies with one shot. However, the max carrying capacity for the Magnum is very low, meaning frequent trips to the ammo dump are necessary. This can prove hazardous to the player. Especially so on Nightmare difficulty, as stopping to reload for any length of time will usually result in death. It's modeled after Taurus Raging Bull and possibly the .44 Magnum Version.
The Magnum is located at the Rest Stop in a storm drain which is located near the trucks underneath the road (to the left of the motel from the road).