Angry Gun MUR-1S upper kit For PTW Outer Barrel 6V or above Battery is

6V or above Battery is recommended

The weapon was originally intended to have used any one of four cartridges: 5

Able to increase the muzzle velocity)  -M16 Voltex Type Flashider (Clockwise) (GP798C)  -Stubby Raider Foregrip (Black) (GP887B)  -Snake-Skin Pistol Grip (Black) (COP033B)  -Troy Style Rear Sight (Black)  -Polymer Trigger Guard (Black) (COP012B)  -Stubby Buttstock (Black) (COP014B)  Mini T-Shape Type Connector Rear Wire Set for Rechargeable Battery located into stock pipe  Maximum can fit 7

The reason being is that the long contact patch nub inside doesn't readjust itself to fit the BB's profile as it gets squeezed through the bucking

the slow where you insert the battery is IN the top rail

Angry Gun MUR-1S upper kit For PTW Outer Barrel 6V or above Battery isAngry Gun MUR 1S upper kit WE Version, PTW Version Made by CNC Material: 6061 Specific Dark White Laser Marking