A system and method of fabricating a percussion tool that includes a choke valve that is replaceable and/or maintainable without disassembly of the percussion tool. The flow tube includes inner and outer walls and at least one opening formed in the outer wall. The inner wall extends from a top end of the flow tube to a bottom end of the flow tube and defines a central channel therein. The outer wall extends from the top end towards the bottom end, surrounds a portion of the inner wall, and defines an outer channel with the inner wall. The choke is positioned at the top end over the central channel and regulate a fluid flow therethrough. A check valve is positioned in fluid communication with the choke.