Firearm operating mechanisms and bolt release

1. An operating system disposed within a receiver of a firearm, the operating system comprising:

a trigger comprising a lower portion, an upper portion, and a trigger pivot;

a hammer comprising a hammer pivot;

a disconnector comprising a lower portion, an upper portion, and a disconnector pivot;

a pivoting arm comprising a forward protrusion, and a pin, wherein at least a portion of the hammer and at least a portion of the disconnector are disposed adjacent to the pivoting arm; and

a lower member comprising a pin hole that is coaxial with the trigger pivot and the disconnector pivot, wherein at least a portion of the trigger and at least a portion of the disconnector are disposed adjacent to the lower member,

wherein motion of the trigger causes the forward protrusion of the pivoting arm to engage a bolt carrier group of the firearm and hold the bolt carrier group in an open position.

2. The operating system of claim 1 , wherein:

the pivoting arm comprises an opening; and

at least a portion of the hammer and at least a portion of the disconnector are disposed within the opening of the pivoting arm.

3. The operating system of claim 1 , wherein the pivoting arm is attached to the lower member by a rotation pin and wherein at least a portion of the pivoting arm is disposed within an opening of the lower member.

4. The operating system of claim 1 , wherein motion of the trigger results in pressure on the pivoting arm pin causing the pivoting arm to move upward and engage the bolt carrier group of the firearm.

5. The operating system of claim 4 , wherein releasing the trigger causes the pivoting arm to move downward and disengage the bolt carrier group of the firearm.

6. The operating system of claim 4 , wherein a subsequent trigger actuation causes the pivoting arm to move downward and disengage the bolt carrier group of the firearm.

7. The operating system of claim 1 , further comprising a disconnector plate, a cam, and a reset arm, wherein:

the disconnector plate is disposed adjacent to the disconnector and comprises a pivot hole that is coaxial with the trigger pivot and the disconnector pivot;

the cam comprises (i) a nose that interfaces with a rear interface portion of the disconnector plate and (ii) a cam pivot that is coaxial with a pin connection between the pivoting arm and the lower member; and

the reset arm comprises a notch that interfaces with a tooth of the cam.

8. The operating system of claim 1 , wherein the hammer pivot is coaxial with a forward pivot hole of the lower member.

9. The operating system of claim 1 , wherein the forward protrusion of the pivoting arm interfaces with a bolt release of the firearm.

10. The operating system of claim 1 , wherein the pivoting arm comprises at least one upward protrusion, wherein the at least one upward protrusion is configured to contact an underside of the bolt carrier group of the firearm.

11. An operating system disposed within a receiver of a firearm, the operating system comprising:

a trigger comprising a lower portion, an upper portion, and a trigger pivot;

a hammer comprising a hammer pivot;

a disconnector comprising a lower portion, an upper portion, and a disconnector pivot; and

a pivoting arm comprising a forward protrusion and a pin, wherein:

motion of the trigger causes the forward protrusion of the pivoting arm to engage a bolt carrier group of the firearm and hold the bolt carrier group in an open position.

12. The operating system of claim 11 , further comprising a lower member that is pivotably attached to the pivoting arm.

13. The operating system of claim 11 , wherein:

the pivoting arm comprises an opening; and

at least a portion of the hammer and at least a portion of the disconnector are disposed within the opening of the pivoting arm.

14. The operating system of claim 11 , wherein motion of the trigger results in pressure on the pivoting arm pin causing the pivoting arm to move upward and engage the bolt carrier group of the firearm.

15. The operating system of claim 14 , wherein releasing the trigger causes the pivoting arm to move downward and disengage the bolt carrier group of the firearm.

16. The operating system of claim 14 , wherein a subsequent trigger actuation causes the pivoting arm to move downward and disengage the bolt carrier group of the firearm.

17. The operating system of claim 11 , further comprising a disconnector plate, a cam, and a reset arm, wherein:

the disconnector plate is disposed adjacent to the disconnector and comprises a pivot hole that is coaxial with the trigger pivot and the disconnector pivot;

the cam comprises (i) a nose that interfaces with a rear interface portion of the disconnector plate and (ii) a cam pivot that is coaxial with a pin connection of the pivoting arm; and

the reset arm comprises a notch that interfaces with a tooth of the cam.

18. The operating system of claim 12 , wherein the hammer pivot is coaxial with a forward pivot hole of the lower member.

19. The operating system of claim 11 , wherein the forward protrusion of the pivoting arm interfaces with a bolt release of the firearm.

20. The operating system of claim 11 , wherein the pivoting arm comprises at least one upward protrusion, wherein the at least one upward protrusion is configured to contact an underside of the bolt carrier group of the firearm.