4- The replica with the two outer barrels Yes, you read that right, it could be said that these models carry two outer barrels, as the outer barrel is divided into two and connected by a part that simulates the gas chamber of a real M4. This, besides joining the two pieces also helps centering the floating barrel. This centering part does not move since it is merged with one of the segments of the barrel. 5- BBs poison A main feature of the mambas is their quick and venomous bite. As it happens with these SRC, and thanks to its Ultra High Torque motor and 8mm bearings, this will provide us with a rate of fire similar to that of the real mamba. This motor is designed to move stiff springs, although this model has a type m100 spring.