Adjustable gas block for an indirect gas operated firearm

A firearm with an adjustable gas block comprising:

• a receiver;
• a barrel connected to the receiver, said barrel having a gas port;
• a gas operating system;
• a nozzle assembly having a front end, back end, middle portion, and internal void with means to communicate with the barrel and gas operating system through a plurality of ports which are spaced about the middle portion, said back end being received within and enveloped by a portion of the gas operating system and having an opening in operational communication with said gas operating system;
• a gas block housing having a barrel receiving channel for a portion of the barrel to be contained therein, a gas nozzle receiving channel having a cylindrical bore which is above and runs parallel to a longitudinal axis of the barrel and the barrel receiving channel, the barrel receiving channel having a port in communication with the barrel, the gas nozzle receiving channel cylindrical bore containing a front portion of the nozzle assembly therein;
• and
• said gas block housing further having a transverse groove formed therein to receive a rotatable knob, said transverse groove running transverse to said barrel axis between the front end of the gas nozzle receiving channel cylindrical bore and a generally planar, rearwardly facing portion of said gas block housing;
• a rotatable knob fitted within said transverse groove and rotatable with respect thereto, said knob having a bore in substantially longitudinal alignment with the gas nozzle receiving channel cylindrical bore, said rotatable knob being coupled to said front portion of said nozzle assembly to retain and control rotational movement of the nozzle assembly.