Method and mechanism for automatic regulation of gas flow when mounting a suppressor to a firearm

1. An auto regulating gas system for an auto loading firearm wherein the firearm includes a barrel having a bore, at least one gas port, and a muzzle, the gas system comprising:

a gas block attached to the barrel to redirect a volume of propellant gases to cycle the auto loading firearm, the gas block including at least one gas port for directing propellant gases received from the at least one gas port of the barrel into the gas system to cycle the auto loading firearm; and

a spring-loaded plunger assembly at least partially positioned within the gas block, the plunger assembly including a plunger component having a plurality of gas ports, and a plunger cap at a forward end, the plunger cap having at least one cam pin and at least one cam path, wherein the position of the plunger component within the gas block automatically controls an amount of gas that is allowed to enter the gas system;

wherein mounting a suppressor to the muzzle depresses the plunger cap and drives it rearwardly causing the plunger component to rotate as the cam pin travels along the cam path to automatically restrict the volume of propellant gases directed into the gas system through a restricted flow gas port in the plunger component.

2. The auto regulating gas system for an auto loading firearm of claim 1 wherein movement of the plunger assembly to restrict the volume of propellant gases enables the firearm to maintain substantially the same bolt velocity in both an unsuppressed condition and in a suppressed condition.

3. The auto regulating gas system for an auto loading firearm of claim 1 wherein a portion of the plunger cap extends past a front end of the gas block towards the muzzle and is driven rearward when the suppressor is mounted to the muzzle, the rearward movement of the plunger cap rotating the plunger component to reduce a flow of propellant gases into the gas system through the restricted flow gas port.

4. The auto regulating gas system for an auto loading firearm of claim 1 further comprising a cross pin inserted into the plunger assembly for retaining the plunger assembly in position in a bore in the gas block.

5. The auto regulating gas system for an auto loading firearm of claim 1 wherein the gas block comprises at least one slot that interfaces with the plunger cap to prevent rotation of the plunger cap during operation of the firearm.

6. The auto regulating gas system for an auto loading firearm of claim 1 wherein the plurality of gas ports in the plunger component comprises a first gas port that aligns with the at least one gas port in the gas block during unsuppressed operation of the firearm, and wherein the restricted flow gas port aligns with the at least one gas port in the gas block during suppressed operation of the firearm.

7. The auto regulating gas system for an auto loading firearm of claim 1 wherein the spring-loaded plunger assembly further comprises a spring located between the plunger component and plunger cap.

8. The auto regulating gas system for an auto loading firearm of claim 7 wherein the spring returns the plunger component and plunger cap to their original position when the suppressor is removed from the muzzle.

9. The auto regulating gas system for an auto loading firearm of claim 7 wherein the spring provides constant tension between the plunger cap and the plunger component preventing movement of the plunger component during unsuppressed operation of the firearm.

10. An auto regulating gas system for an auto loading firearm including a barrel having a bore, at least one gas port, and a muzzle, the gas system comprising:

a gas block attached to the barrel and including at least one gas port for directing propellant gases received from the at least one gas port of the barrel into the gas system to cycle the auto loading firearm and a passageway connected to the at least one gas port of the gas block;

a flow regulator at least partially positioned in the gas block, the flow regulator comprising a regulator body rotatably positioned in the passageway of the gas block, wherein the position of the regulator body within the passageway controls an amount of gas that is allowed to enter the gas system; and

a plunger part configured to project from the gas block a distance sufficient to be engaged and moved rearwardly upon mounting of a suppressor to the muzzle of the firearm barrel;

wherein the regulator body is moved in the passageway of the gas block a distance sufficient to adjust a volume of gas allowed to enter the gas system in response to the plunger part being engaged and moved rearwardly by the suppressor.

11. The auto regulating gas system for an auto loading firearm of claim 10 wherein:

the regulator body is mounted for rotating within the passageway;

the plunger part is mounted for reciprocating; and

the gas system further comprises a cam and a cam follower configured to cause rotation of the flow regulator in response to reciprocation of the plunger part.

12. The auto regulating gas system for an auto loading firearm of claim 11 wherein:

the plunger part is biased forwardly by at least one spring; and

the regulator body has a plurality of gas ports configured for being respectively open to the at least one gas port in the gas block in response to rotation of the regulator body.

13. The auto regulating gas system for an auto loading firearm of claim 10 wherein movement of the regulator body to adjust the volume of propellant gases allowed to enter the gas system enables the firearm to maintain substantially the same bolt velocity in both an unsuppressed condition and in a suppressed condition.

14. The auto regulating gas system for an auto loading firearm of claim 10 wherein a portion of the plunger part extends past a front end of the gas block towards the muzzle and is driven rearward when the suppressor is mounted to the muzzle, the rearward movement of the portion of the plunger part rotating the regulator body to reduce a flow of propellant gases into the gas system through the at least one gas port of the gas block.

15. The auto regulating gas system for an auto loading firearm of claim 10 further comprising a cross pin engaged between the flow regulator and the gas block for at least partially retaining the flow regulator in the gas block.

16. The auto regulating gas system for an auto loading firearm of claim 10 wherein the gas block comprises at least one slot that interfaces with the plunger cap to restrict rotation of the plunger cap.

17. The auto regulating gas system for an auto loading firearm of claim 10 wherein the regulator body comprises a first gas port that aligns with the at least one gas port in the gas block during unsuppressed operation of the firearm, and wherein the restricted flow gas port aligns with the at least one gas port in the gas block during suppressed operation of the firearm.

18. A method of regulating a gas system for an auto loading firearm, the method comprising:

mounting a suppressor to a muzzle of a barrel of the firearm;

engaging a linkage with the suppressor, and in response, moving the linkage to rotate a flow regulator in a gas flow passage; and

adjusting an amount of gas that is allowed to enter the gas system in response to the rotation of the flow regulator.

19. The method of claim 18 wherein the rotating of the flow regulator is comprised of rotating a body of the flow regulator so that a first gas port of the body becomes closed from at least one gas port of a gas block and a second gas port of the body becomes open to the at least one gas port of the gas block.