Side-charging upper for AR style firearm

1. A side charging assembly for an AR style firearm, the assembly comprising:

a. a pull knob having a first axis substantially perpendicular to a bore axis of the firearm and a second axis substantially parallel to the bore axis of the firearm;

wherein the pull knob comprises 3 channels which extend the length of the pull knob on the first axis;

wherein the pull knob comprises faces on the first axis that are substantially elliptical; and

wherein an exterior profile of the pull knob on the second axis is concave on at least a portion of a forward and/or rearward edge of the pull knob; and

b. a charging hook comprising

i. a charging hook body comprising:

1. pull knob connection face, comprising 3 threaded channels;

2. a piston rod channel on a rearward surface of the charging hook body; and

ii. a bolt carrier connection portion configured to engage a charging handle contact point of a bolt carrier.

2. The side charging assembly of claim 1 , wherein the bolt carrier connection portion has a flat upper edge.

3. The side charging assembly of claim 1 , wherein the 3 channels of the pull knob do not comprise threading.

4. The side charging assembly of claim 1 , wherein the exterior profile of the pull knob on the second axis is concave on at least a portion of both the forward and rearward edges.

5. The side charging assembly of claim 1 , further comprising:

c. a piston rod comprising a solid cylindrical body and rear portion comprising a smaller solid cylinder;

d. a piston guide tube comprising

i. a cylindrical body;

ii. an interior piston rod channel, configured to accept the piston rod and a push spring in a front of the cylindrical body of the piston guide tube;

e. the push spring located inside the piston rod channel of the piston guide tube and captured on the rear portion of the piston rod, whereby the push spring exerts force to hold the piston rod in a forward position relative to the piston guide tube; and

f. a return spring positioned rearward of the piston guide tube which exerts force to hold the piston rod guide tube, the piston rod, the charging hook, and the pull knob in the forward position.

6. The side charging assembly of claim 5 , wherein the piston guide tube comprises a closed rear face to retain the push spring.

7. The side charging assembly of claim 5 , wherein the piston guide tube comprises two holes in the cylindrical body and a pin extending between the two holes to retain the push spring.

8. The side charging assembly of claim 7 , wherein the pin is a roll pin.

9. The side charging assembly of claim 1 , wherein the side charging assembly does not comprise a detent in the pull knob.

10. The side charging assembly of claim 1 , wherein the side charging assembly does not comprise a detent which engages the pull knob with an upper receiver body.

11. A side-charging upper receiver assembly for an AR style firearm, the side-charging upper receiver assembly comprising:

a. an upper receiver body with a channel opening formed in a side of the body;

b. a bolt carrier operatively coupled within the upper receiver body;

c. a bolt coupled within the bolt carrier;

d. the side charging assembly of claim 1 , whereby the pull knob that extends through the channel opening of the upper receiver body and which moves the bolt carrier toward a butt stock of the firearm in response to the pull knob being moved toward the butt stock of the firearm.

12. The upper receiver assembly of claim 11 , wherein the upper receiver body further comprises a gas key channel wherein the rear end of the gas key channel comprises threads to accept a set screw.

13. The upper receiver assembly of claim 12 , further comprising the set screw engaged in the threads.

14. The upper receiver assembly of claim 11 , further comprising a deflector rearward of an ejection port on an exterior side of the upper receiver body.