Buffer extension

1. A buffer extension for a firearm that includes a buffer, a buffer spring, and a bolt carrier group, the buffer extension comprising:

a body comprising a front face, a rear face, a length extending from the front face to the rear face, at least one hole extending along the length, at least one weight disposed within the at least one hole, and an outer surface, wherein:

an entirety of the buffer extension is disposed between a forwardmost face of the buffer and a rearmost surface of the bolt carrier group;

the rear face of the buffer extension contacts the forwardmost face of the buffer when the buffer is pushed to a forwardmost position by the buffer spring and during rearward movement of the buffer;

the front face of the buffer extension contacts the rearmost surface of the bolt carrier group; and

the buffer extension increases both the effective mass and the effective length of the buffer.

2. The buffer extension of claim 1 , wherein the at least one hole comprises at least four holes.

3. The buffer extension of claim 1 , wherein the front face comprises a groove that intersects at least a portion of the at least one hole.

4. The buffer extension of claim 3 , further comprising an O-ring disposed within the groove.

5. The buffer extension of claim 4 , wherein, when the O-ring is disposed within the groove, the O-ring is approximately flush with the front face.

6. The buffer extension of claim 1 , wherein a material of the at least one weight comprises at least one selected from the group of steel, tungsten, and tungsten carbide.

7. The buffer extension of claim 1 , wherein the at least one weight has a length that is less than a length of the at least one hole.

8. The buffer extension claim 1 , wherein the at least one weight moves within the at least one hole during movement of the buffer to create a dead blow effect.

9. The buffer extension of claim 1 , wherein a length of the body is 17 mm to 20 mm.

10. A buffer extension for a firearm that includes a buffer, a buffer spring, and a bolt carrier group, the buffer extension comprising:

a cylindrical body comprising a front face, a rear face, a length extending from the front face to the rear face, a plurality of holes extending along the length, and an outer surface, wherein:

an entirety of the buffer extension is disposed between a forwardmost face of the buffer and a rearmost surface of the bolt carrier group;

the rear face of the buffer extension contacts the forwardmost face of the buffer when the buffer is pushed to a forwardmost position by the buffer spring and during rearward movement of the buffer; and

the front face of the buffer extension contacts the rearmost surface of the bolt carrier group.

11. The buffer extension of claim 10 , wherein the front face comprises a groove that intersects at least a portion of the plurality of holes.

12. The buffer extension of claim 11 , further comprising an O-ring disposed within the groove.

13. The buffer extension of claim 12 , wherein, when the O-ring is disposed within the groove, the O-ring is approximately flush with the front face.

14. The buffer extension of claim 10 , further comprising at least one weight disposed within the plurality of holes.

15. The buffer extension of claim 14 , wherein a material of the at least one weight comprises at least one selected from the group of steel, tungsten, and tungsten carbide.

16. The buffer extension of claim 14 , wherein the at least one weight has a length that is less than a length of the plurality of holes.

17. The buffer extension of claim 14 , wherein the at least one weight moves within the plurality of holes during movement of the buffer to create a dead blow effect.

18. A buffer extension comprising:

a body comprising at least one face, an outer surface, and at least one hole extending along a length of the body, wherein the face comprises a groove that intersects at least a portion of the at least one hole; and

an O-ring disposed within the groove,

wherein the body is disposed between and contacts at least one of a buffer and a bolt carrier group such that the body increases both the effective mass and the effective length of the buffer.