Firearm accessory mounting system

1. An adaptor system for mounting an accessory to a firearm, the adaptor system comprising:

a firearm barrel comprising a bore and a muzzle end, the bore comprising a first diameter sized for a projectile to be fired therethrough, the muzzle end comprising an opening through which the projectile may be ejected,

wherein an interior of the muzzle end comprises:

a first plurality of lugs extending radially inwardly adjacent the opening;

a plurality of slots interposed between the first plurality of lugs; and

an annular groove positioned behind the first plurality of lugs;

an adaptor comprising a longitudinally extending shaft and a second plurality of lugs, the second plurality of lugs extending radially outwardly from the shaft and sized to be inserted longitudinally through the plurality of slots of the muzzle end of the firearm barrel,

wherein the shaft of the adapter is rotatable within the interior of the muzzle end of the firearm barrel such that at least a portion of the second plurality of lugs can be positioned within the annular groove, with a forward portion of the second plurality of lugs being in contact with a rearward portion of the first plurality of lugs; and

a biasing member positioned to bias the adapter in a longitudinal direction away from the bore of the firearm barrel, such that the forward portion of the second plurality of lugs will remain in contact with the rearward portion of the first plurality of lugs.

2. The adapter system of claim 1 , wherein the biasing member comprises an annular spring.

3. The adapter system of claim 2 , wherein the annular spring is positioned about the shaft of the adapter.

4. The adapter system of claim 3 , wherein the annular spring is positioned longitudinally between the second plurality of lugs and a flange of the adapter.

5. The adapter system of claim 1 , further comprising a locking jam configured to maintain the adapter in a rotational orientation with respect to the barrel, the locking jam comprising:

at least one internal flute shaped to engage a protrusion that protrudes radially from the shaft of the adapter; and

at least one longitudinally protruding member shaped to engage a longitudinally recessed portion of the muzzle end of the firearm barrel.

6. The adapter system of claim 5 , wherein the biasing member comprises an annular spring positioned about the shaft of the adapter.

7. The adapter system of claim 6 , wherein the annular spring is positioned longitudinally between the locking jam and a flange of the adapter.

8. The adapter system of claim 1 , wherein the adapter further comprises a mounting component configured to receive an accessory.

9. The adapter system of claim 8 , wherein the mounting component comprises a thread configured to receive a threaded portion of the accessory.

10. The adapter system of claim 1 , wherein the adapter further comprises an accessory comprising at least one of the following: a compensator, a silencer, or a flash suppressor.

11. The adapter system of claim 1 , wherein the firearm barrel further comprises a chamber end positioned at an opposite end from the muzzle end, the chamber end comprising a cavity sized for positioning therein of a projectile cartridge.

12. The adapter system of claim 1 , wherein an innermost surface of the first plurality of lugs defines a second diameter that is larger than the first diameter of the bore of the firearm barrel.

13. A firearm barrel for use in a quick release accessory adapter system, the firearm barrel comprising:

a bore comprising a diameter sized for a projectile to be fired therethrough; and

a muzzle end comprising an opening through which the projectile may be ejected,

wherein an interior of the muzzle end comprises:

a plurality of lugs extending radially inwardly adjacent the opening;

a plurality of slots interposed between the plurality of lugs; and

a radially outwardly extending annular groove positioned behind the plurality of lugs, for positioning of complementary lugs of a component separable from the firearm barrel, and

wherein a forward-most face of the muzzle end further comprises at least one longitudinally recessed or protruding portion for engaging a complementary portion of a locking jam to rotationally orient the locking jam with respect to the muzzle end.

14. The firearm barrel of claim 13 , wherein the at least one longitudinally recessed or protruding portion of the muzzle end comprises a recess that extends rearward from the forward-most face of the muzzle end of the firearm barrel.

15. The firearm barrel of claim 13 , wherein the at least one longitudinally recessed or protruding portion of the muzzle end comprises a plurality of longitudinally recessed portions spaced about the forward-most face of the muzzle end.

16. The firearm barrel of claim 13 , wherein the radially outwardly extending groove comprises an annular groove comprising a diameter that is larger than the diameter of the bore.

17. The firearm barrel of claim 13 , further comprising a chamber end positioned at an opposite end from the muzzle end, the chamber end comprising a cavity sized for positioning therein of a projectile cartridge.