Multi-Part Buffer Tubes, Methods of Manufacturing the Same, and Firearms Including the Same
Multi-part buffer tubes, methods of manufacturing the same, and firearms including the same are disclosed. In embodiments the multi-part buffer tube includes a cap, and a body that includes a tube. The tube may include a wall with an outward facing side, an inward facing side, a first end, and a second end. The inward facing side of the wall may define a cavity for receiving a buffer and a buffer spring for a firearm. The cap that is coupled to the body in any suitable manner For example, at least a portion of the cap may be disposed within a channel formed in the inward facing side of the tube, e.g., proximate the first end of the wall.
The present disclosure relates to buffer tubes for firearms, methods of forming the same, and firearms including the same. More particularly, the present disclosure relates to multi-part buffer tubes, methods of forming the same, and firearms including the same.
BACKGROUNDModular gas operated small arms such as the M16, the M4, and the AR-15, are popular with civilians, law enforcement agencies, militaries, and the like. Part of their appeal is attributable to their modular nature, which allows users to customize the weapon to achieve a desired aesthetic and/or functional goal.
During normal operation of an AR-15 style rifle such as rifle 100, propellant in cartridge ammunition is detonated to produce gas that forces a bullet out of the barrel of the rifle. Before the bullet exits the barrel a portion of the gas enters a gas port in the barrel.
The gas port directs the gas into a tube, which conveys the gas into a cylinder between the bolt carrier and the bolt of the rifle. The gas drives the bolt carrier rearward (towards the buttstock 105). This forces the buffer 117 (which is pressing against the bolt carrier) rearward against buffer spring 115 and toward first end 102, allowing the bolt carrier to continue to move rearward. During this continued rearward movement of the bolt carrier, a spent cartridge is extracted from the chamber and expelled through an ejection port of the rifle. When the bolt carrier reaches a rearmost position (e.g., when the buffer 117 contacts first end 102), the compressed buffer spring 115 expands, driving the buffer 117 forward with enough force to drive the carrier bolt forward toward the chamber. During the return of the bolt carrier towards the chamber, a new cartridge is picked up by the bolt from a magazine and pushed forward to chamber the new cartridge.
Buffer tubes such as buffer tube 111 are single-piece (i.e., monolithic) parts, meaning that all parts of the buffer tube are integrally formed from a single piece of metal. For example, manufacturing of buffer tube 111 may begin with a metal billet, such as a billet of aluminum or titanium. The billet may be machined (e.g., using lathes, drills, milling machines, honing machines, grinders, etc.) to form a single piece part that includes the cylindrical portion, keyed protrusion 113, and first end 102 of buffer tube 111. Although traditional single-piece buffer tubes are useful, machining such buffer tubes from a metal billet may require the use of specialized machinery and personnel, which can lead to increased manufacturing costs. Since billets are typically solid, the manufacturing process results in the generation of considerable metal waste, which must be disposed of or recycled.
Accordingly, a need remains in the art for improved buffer tubes for use in gas operated firearms, and methods of making the same. The present disclosure is aimed at such needs.
The above-mentioned and other features of this disclosure, and the manner of attaining them, will become more apparent and better understood by reference to the following description of embodiments described herein taken in conjunction with the accompanying drawings, wherein:
The present disclosure is not limited in its application to the details of construction and the arrangement of components set forth in the following description or illustrated in the drawings. The invention(s) herein may be capable of other embodiments and of being practiced or being carried out in various ways. Also, it may be appreciated that the phraseology and terminology used herein is for the purpose of description and should not be regarded as limiting as such may be understood by one of skill in the art.
As described in the background, traditional buffer tubes are single-piece (i.e., monolithic) parts that are generally manufactured by machining a block of material such as a metal billet. Although single-piece buffer tubes are useful, how they are made can increase their cost and generate substantial waste. With that in mind, aspects of the present disclosure relate to multi-part buffer tubes, firearms including the same, and methods of forming the same. As will become apparent from the following disclosure, the multi-part buffer tubes described herein may be manufactured in accost effective manner that generates less waste than the manufacturing process of traditional buffer tubes, while still achieving desired performance.
In embodiments the multi-part buffer tubes described herein include a body that includes a tube. The tube may include a wall with an outward facing side, an inward facing side, a first end, and a second end. The inward facing side of the wall may define a cavity for receiving a buffer and a buffer spring for a firearm. The buffer tubes described herein further include a cap that is coupled to the body in any suitable manner. For example, at least a portion of the cap may be disposed within a channel formed in the inward facing side of the tube, e.g., proximate the first end of the wall.
In embodiments the multi-part buffer tube further includes a lip between the channel and the first end of the tube. The lip may have an inner diameter ID1, the channel may have an inner diameter ID2, wherein ID2 is greater than ID1. In those or other embodiments the cap includes a first cap part and a second cap part wherein at least a portion of the second cap part may be disposed within the channel. The first cap part may have an outer diameter OD3, the second cap part may have an outer diameter OD4, wherein OD4 is greater than OD3. In embodiments, the first cap part is positioned proximate the lip and OD3 is the same or about the same as ID1. In those or other embodiments, the cap may further include a cap groove between the first cap part and the second cap part.
The cap may include a first cap side facing away from the cavity of the tube, and a second cap side that faces towards the cavity. In such embodiments the first side may be coplanar or substantially coplanar with a surface of the first end of the tube.
The multi-part buffer tubes described herein may also include threads that are formed on the outward facing side of the tube. In such instances the first end of the tube may have an outer diameter OD1 and the threads may have an outer diameter OD2, wherein OD2>OD1.
Another aspect of the present disclosure relates to methods of forming multi-part buffer tubes for a firearm. In embodiments, the methods include providing a body that includes a tube that includes a wall with an outward facing side, an inward facing side, a first end, a second end, and a channel formed in the inward facing side proximate the first end, wherein the inward facing side defines a cavity for receiving a buffer and a buffer spring for a firearm. The method further includes providing a cap, and coupling the cap to the tube within the cavity. In embodiments, coupling the cap to the tube includes deforming (e.g., by compressing) the cap such that at least a portion of the cap is disposed within the channel. The cap and tube may have any or all the features of the caps and tubes described herein in connection with a multi-part buffer tube.
Another aspect of the present disclosure relates to a firearm. The firearm includes a lower receiver, an upper receiver, and a multi-part buffer tube. The multi-part buffer tube may include any or all the features of the multi-part buffer tubes described herein.
Reference is now made to
The keyed protrusion 313 extends from tube 301 (e.g., at a six o'clock or other position). In general, keyed protrusion 313 is configured to facilitate coupling of multi-part buffer tube 300 to a firearm, such as a firearm receiver, buttstock, or combination thereof. For example, the keyed protrusion 313 may include a groove and/or a plurality of recesses (not labeled) that are configured to set the position of a buttstock or receiver of a firearm relative to the multi-part buffer tube 300.
As further shown in
Multi-part buffer tube 300 further includes a cap 305 that is coupled to tube 301. Cap 305 is generally configured to provide a surface against which a buffer spring may be compressed when a bullet is fired by a firearm in which multi-part buffer tube 300 is installed. Cap 305 may be coupled to tube 301 in any suitable manner, such as via an interference fit with tube 301, a weld, an adhesive, a mechanical fastener, combinations thereof, and the like. For example, cap 305 may be coupled to tube 301 via threads, wherein the threads on Cap 305 may have a larger or smaller diameter than mating threads on ID1 of tube 301. Without limitation, cap 305 is coupled to tube 301 at least in part due to interference between a part of cap 305 and a part of tube 301. Notably and as distinguished from traditional buffer tubes, tube 301 and cap 305 are not integral parts, but rather are at least two distinct pieces that are joined together to form a multi-part buffer tube consistent with the present disclosure. This may be evidenced by the presence of a seam or other interface between the cap 305 and the tube 301.
Without limitation, cap 305 is configured to be installed proximate first end 302 of tube 301, as best shown in
As noted above, cap 305 is preferably coupled to tube 301 via an interference fit with tube 301. In that regard reference is made to
As further shown in
The cross-sectional shape of channel 309 is not limited, and channel 309 may have any suitable cross sectional shape. For example, channel 309 may have a one, two, three, four, or more sided geometric cross sectional shape, an irregular cross sectional shape, or a combination thereof. Without limitation, in embodiments channel 309 has a c-shaped (three sided) cross sectional shape. The depths of channel 309 is also not limited, and channel 309 may have any suitable depth provided it is less than the thickness of the wall defining the cavity within tube 301. In embodiments, the depth of channel 309 ranges from greater than 0 to less than or equal to about .0.050 inches, such as from greater than 0 to about 0.040 inches, greater than 0 to about 0.030 inches, or even greater than 0 to about 0.015 inches.
For example, in embodiments cap 305 and tube 301 may be initially provided as separate parts, e.g., as shown in
With reference to
As noted above, cap 305 may include a cap groove 329 between a first cap part 325 and a second cap part 327. In general, cap groove 329 is configured to facilitate deformation of second cap part 327 into channel 309 during the formation of multi-part buffer tube 300. For example, and as will be described further below in connection with
As noted above and as best shown in
Cap 305 and tube 301 may be configured such that cap 305 is positioned in a desirable manner relative to one another when they coupled. For example, cap 305 and channel 309 may be configured such that following coupling of cap 305 to tube 301, first cap side 321 is parallel, substantially parallel, and/or coplanar with first end 302 of tube 301, as shown in
Moreover, and as also shown in
Body 310, tube 301, and cap 305 may be formed from any suitable material. Non-limiting examples of such materials include metals such as aluminum, titanium, iron, and the like, and alloys such as steel, brass, and the like. Other materials may also be used, as would be understood by those of ordinary skill in the art. In embodiments, body 310, tube 301, and cap 305 are each formed from aluminum.
For the sake of illustration and ease of understanding, the description of
Another aspect of the present disclosure relates to a firearm that includes a multi-part buffer tube assembly consistent with the present disclosure. In embodiments the firearm includes at least a lower receiver, an upper receiver, and multi-part buffer tube consistent with the present disclosure. In embodiments, the firearm is a modular rifle such as an M4, M16, or AR-15 style rifle, but the present disclosure is not limited thereto. The construction of such rifles is well understood and thus is not described. In any case the multi-part buffer tubes used in such rifles have the same features as described above. As such, the features of such multi-part buffer tubes are not re-described in the interest of brevity.
Another aspect of the present disclosure relates to methods of making a multi-part buffer tube. In that regard reference is made to
Following the operations of block 403 or if such operations are omitted (e.g., where a cap and/or tube are provided by a third party), the method may proceed to block 405, pursuant to which the cap and tube are joined. As noted above the cap and tube may be joined in any suitable manner. Without limitation, in embodiments the cap and tube are joined by deforming at least a portion of the cap to create an interference fit joint between the cap and the tube or, more particularly, between a channel formed in an inward facing side of the tube and the cap. For example, and as shown in
A compression support 505 may then be arranged over the first end 302. As generally shown in
Once compression support 505 is positioned on the first end 302 as shown in
As noted above, first compression surface 504 may include a stepped pin structure (e.g., a chamfer, bevel, protrusion, etc.) 506. In embodiments, the angle and/or length of stepped pin structure 506 may differ from the angle and/or length of stepped cap structure 330, to facilitate radial outward deformation of second cap part 327 into channel 309. For example, the inside angle of stepped pin structure 506 may be greater than 0 to about 15 degrees steeper than the outside angle of stepped cap structure 330 at a point 530, to encourage such radially outward deformation of second cap part 327 into channel 309.
Returning to
As used herein, the term “about” when used in connection with a number or a range, means +/−5% of the indicated number or the endpoints of the indicated range.
As used herein, the term “coplanar” when used to describe the positions of a first surface and a second surface, means that the first and second surfaces lie in and extend along the same plane. In contrast, the term “parallel” when used to describe the relative positions of a first surface and a second surface, means that the first surface lies along a first plane, and the second surface lies along a second plane that extends in the same direction as the first plane but which is offset from the first plane. The term “substantially parallel” means that the first and second surfaces extend along planes that are offset from one another and which are within +/−5 degrees of parallel relative to one another.
The foregoing description of the embodiments of the invention has been presented for the purposes of illustration and description. Each and every page of this submission, and all contents thereon, however characterized, identified, or numbered, is considered a substantive part of this application for all purposes, irrespective of form or placement within the application. This specification is not intended to be exhaustive or to limit the invention to the precise form disclosed. Many modifications and variations are possible in light of this disclosure.
Claims
1. A multi-part buffer tube for a firearm, comprising:
- a body comprising a tube, the tube comprising a wall with an outward facing side, an inward facing side, a first end, and a second end; and
- a cap coupled to the tube by way of deformation to form an interference fit joint;
- wherein:
- the inward facing side of the wall defines a cavity for receiving a buffer and a buffer spring; and
- at least a portion of the cap is disposed within a channel formed in the inward facing side proximate the first end of the wall.
2. The multi-part buffer tube of claim 1, further comprising a lip between the channel and the first end; wherein:
- the lip has an inner diameter ID1;
- the channel has an inner diameter ID2; and
- ID2>ID1.
3. The multi-part buffer tube of claim 2, wherein:
- the cap comprises a first cap part and a second cap part; and
- at least a portion of the second cap part is disposed within the channel.
4. The multi-part buffer tube of claim 3, wherein:
- the first cap part has an outer diameter OD3;
- the second cap part has an outer diameter OD4; and
- OD4>OD3.
5. The multi-part buffer tube of claim 4, wherein:
- the first cap part is positioned proximate the lip; and
- OD3 equals or is about equal to ID1.
6. The multi-part buffer tube of claim 3, wherein the cap portion further comprises a cap groove between the first cap part and the second cap part.
7. The multi-part buffer tube of claim 4, wherein the cap portion further comprises a cap groove between the first cap part and the second cap part.
8. The multi-part buffer tube of claim 3, wherein:
- the cap portion comprises a first cap side facing away from the cavity and a second cap side facing towards the cavity; and
- the second cap side comprises at least one stepped cap structure.
9. The multi-part buffer tube of claim 3, wherein:
- the cap portion comprises a first cap side facing away from the cavity and a second cap side facing towards the cavity; and
- the first cap is coplanar or substantially coplanar with the first end.
10. The multi-part buffer tube of claim 1, further comprising threads formed on the outward facing side of the wall proximate the second end;
- wherein:
- the first end has an outer diameter OD1;
- the threads have an outer diameter OD2; and
- OD2>OD1.
11. A method of manufacturing a multi-part buffer tube for a firearm, comprising:
- providing a body comprising a tube, the tube comprising a wall with an outward facing side, an inward facing side, a first end, a second end, and a channel formed in the inward facing side proximate the first end, the inward facing side defining a cavity for receiving a buffer and a buffer spring of a firearm;
- providing a cap; and
- coupling the cap to the tube within the cavity by way of deformation to form an interference fit joint.
12. The method of claim 11, wherein coupling the cap to the tube comprises deforming the cap such that at least a part of the cap is disposed within the channel.
13. The method of claim 11, wherein:
- providing the cap comprises providing a cap comprising a first cap part, and a second cap part, the first cap part having first outer diameter and the second cap part having a second outer diameter; and
- following said coupling, at least a portion of the second cap part has a third outer diameter that is greater than the second outer diameter.
14. The method of claim 13, wherein the first outer diameter equals or is about equal to the second outer diameter.
15. The method of claim 13, wherein:
- the tube further comprises a lip between the channel and the first end;
- the lip has a first inner diameter; and
- the channel has a second inner diameter than is greater than the first inner diameter.
16. The method of claim 11, wherein coupling the cap to the tube comprises compressing the cap.
17. A firearm, comprising a lower receiver, an upper receiver, and a multi-part buffer tube, the multi-part buffer tube comprising: wherein:
- a body comprising a tube, the tube comprising a wall with an outward facing side, an inward facing side, a first end, and a second end; and
- a cap coupled to the tube by way of deformation to form an interference fit joint;
- the inward facing side of the wall defines a cavity for receiving a buffer and a buffer spring; and
- at least a portion of the cap is disposed within a channel formed in the inward facing side proximate the first end of the wall.
18. The firearm of claim 17, wherein the multi-part buffer tube further comprises a lip between the channel and the first end; wherein:
- the lip has an inner diameter ID1;
- the channel has an inner diameter ID2; and
- ID2>ID1.
19. The firearm of claim 17, wherein:
- the cap comprises a first cap part and a second cap part; and
- at least a portion of the second cap part is disposed within the channel.
20. The firearm of claim 19, wherein:
- the first cap part has an outer diameter OD3;
- the second cap part has an outer diameter OD4; and
- OD4>OD3.
21. The firearm of claim 20, wherein:
- the first cap part is positioned proximate the lip; and
- OD3 equals or is about equal to ID1.
22. The firearm of claim 19, wherein the cap portion further comprises a cap groove between the first cap part and the second cap part.
23. The firearm of claim 19, wherein:
- the cap portion comprises a first cap side facing away from the cavity and a second cap side facing towards the cavity; and
- the second cap side comprises at least one stepped cap structure.
24. The firearm of claim 19, wherein:
- the cap portion comprises a first cap side facing away from the cavity and a second cap side facing towards the cavity; and
- the first cap is coplanar or substantially coplanar with the first end.
25. The firearm of claim 17, further comprising threads formed on the outward facing side of the wall proximate the second end;
- wherein:
- the first end has an outer diameter OD1;
- the threads have an outer diameter OD2; and
- OD2>OD1.
26. The multi-part buffer tube of claim 1, wherein at least a portion of the cap is deformed into the channel to form the interference fit joint.
27. The method of claim 11, wherein at least a portion of the cap is deformed into the channel to form the interference fit joint.
28. The multi-part buffer tube of claim 17, wherein at least a portion of the cap is deformed into the channel to form the interference fit joint.
Type: Application
Filed: May 28, 2021
Publication Date: Dec 1, 2022
Inventors: Norman Binz Dewalch (Houston, TX), Tyler Dean Todd, II (Houston, TX)
Application Number: 17/334,201