US Patent 10203178 Firearm chassis with integrated rail system

A chassis for a firearm includes sidewalls, a forearm, and a first rail portion. The sidewalls define a trigger well and a magazine well therebetween. The sidewalls also define a proximal portion of a channel. The forearm is monolithically formed with the chassis and extends distally from the magazine well. The forearm defines a distal portion of the channel which is configured to receive a barrel of a firearm. The first rail portion extends from the forearm adjacent the channel on a first side of the chassis. The first rail portion defines part of a rail system that is configured to securely mount an accessory directly to the chassis.