Bolt mechanisms and firearms containing the same

Abstract

A firearm includes a bolt mechanism with a bolt configured to receive a firing pin assembly and a bolt head assembly. The bolt head assembly includes a pivoting bolt head and an extractor. The extractor is positioned relative to the bolt such that substantially all forces applied by the extractor to the bolt mechanism are reacted within the bolt head assembly. A biasing member or element can urge a claw portion of extractor towards a distal end of the bolt head.

Description

TECHNICAL HELD

The present invention relates generally to bolt mechanisms for firearms. More specifically, the invention relates to bolt mechanisms having an extractor and firearms containing the same.

BACKGROUND

Bolt-action rifles often have extractors for receiving cartridges from magazines and removing empty cartridge shells from firing chambers. U.S. Pat. No. 467,180 discloses a bolt system that includes an extractor for removing empty cartridge shells. The extractor is pivotally coupled to a bolt head such that a rearward end of the extractor contacts an outer surface of a bolt. The bolt reacts the force applied by the rearward end of the extractor such that the extractor body provides a spring force. Because the bolt reacts the forces applied by the extractor, the bolt is fixedly coupled to the bolt head to ensure that the bolt head is properly aligned. Unfortunately, bolt heads often improperly seat with the body of the barrel, thereby impairing performance of the rifle. For example, gaps between lugs of the bolt head and breech (or barrel extender) may result in movement of components (e.g., bolt head and bolt) and misalignment of the bolt face and/or excessive wear/damage when large pressures build up in the firing chamber during firing.

SUMMARY

At least some embodiments disclosed herein are directed to a bolt mechanism including a bolt and a bolt head assembly. The bolt head assembly includes a floating bolt head and an extractor. Substantially all loads applied by the extractor can be reacted within the bolt head assembly. For example, the extractor can receive and hold shells of cartridges without applying forces directly to the bolt. The bolt head assembly can internally react forces associated with movement of the extractor to, for example, maintain contact between the bolt head and other component(s) of the firearm. In some embodiments, the bolt head rotates relative to the bolt to keep a bearing surface of lugs of the bolt head assembly substantially flat against a shoulder (e.g., a bearing shoulder which is part of the receiver, barrel extension, barrel, breech, etc.) or other feature(s) for bearing loads, such as loads imparted by pressures during firing.

The extractor, in some embodiments, is biased against the bolt head without applying loads directly to the bolt, and the extractor can be moved without influencing seating of the bolt head. The extractor can be biased by a biasing member, including one or more integral biasing members (e.g., cantilevered portions) or springs. The bolt head, in some embodiments, can pivot relative to the bolt about two axes of rotation. The axes of rotation can be generally perpendicular to one another or at other suitable orientations. In one embodiment, the bolt head can rotate while the bolt is in a locked position to seat the lugs (e.g., locking lugs) against bearing surfaces of, for example, a barrel, a barrel extension, or other component of the firearm.

In some embodiments, a bolt mechanism for a firearm includes a bolt and a bolt head assembly. The bolt is configured to receive a firing pin assembly. The bolt head assembly is coupled to a bolt and includes a bolt head and an extractor. The bolt head assembly is configured to react substantially all forces applied to the bolt mechanisms by the extractor. In one embodiment, the extractor is pivotally coupled to a collar of the bolt head assembly. A biasing member can urge the extractor towards an engagement position such that a claw portion of the extractor is positioned to receive a shell (or case) of a cartridge. The bolt head can be pivotally coupled and translationally fixed to the bolt.

In some embodiments, a bolt mechanism includes a bolt, a bolt head, and an extractor. The extractor can only contact surfaces of a bolt head assembly. The extractor can be biased without applying a force or a torque that causes relative movement between the bolt and the bolt head.

In some embodiments, a bolt mechanism for a firearm includes a bolt and a bolt head assembly. The bolt has a longitudinal axis of rotation. The bolt head assembly is coupled to the bolt and includes a bolt head and an extractor. The extractor is non-rotating about the longitudinal axis of the bolt. In one embodiment, the extractor is positioned relative to the bolt such that substantially all forces associated with, for example, biasing of the extractor. In one embodiment, all of the forces applied by the extractor to the bolt mechanism are reacted within the bolt head assembly while the bolt mechanism is positioned in the firearm.

In one embodiment, the extractor can slide proximally or distally as the bolt mechanism is moved proximally or distally, respectively. While the bolt is rotated, the extractor can be non-rotating about the bolt longitudinal axis. In certain embodiments, the bolt head assembly includes a pin and a non-rotating collar positioned between a head portion of the bolt head and the bolt. The pin rotatably couples the extractor to the non-rotating collar.

A bolt mechanism can include a bolt and a bolt head assembly. The bolt is configured to receive a firing pin assembly and has a longitudinal axis of rotation. The bolt head assembly is coupled to the bolt and includes a floating bolt head and an extractor. The extractor is non-rotating about the longitudinal axis of the bolt mechanism or an axis of a firearm. When the bolt mechanism is moved from an open position and a closed position, the extractor translates (without rotation about the longitudinal axis of the bolt) along the firearm.

In some embodiments, a bolt mechanism includes a bolt having a longitudinal axis and a separate bolt head assembly coupled to the bolt. The bolt head assembly includes an extractor rotatable about the longitudinal axis of the bolt when the bolt head assembly is uninstalled. In one embodiment, the bolt head assembly further comprises a floating bolt head. The extractor is positioned relative to the bolt such that substantially all forces applied by the extractor to the bolt mechanism are reacted within the bolt head assembly when the bolt mechanism is positioned in the firearm. The bolt head assembly further comprises a floating bolt head that is rotatable about two axes of rotation. The two axes can be substantially perpendicular to the longitudinal axis.

In certain embodiments, the bolt mechanism includes a bolt, a pin, and a bolt head assembly. The bolt is configured to receive a firing pin assembly and has a longitudinal axis. The bolt head assembly includes a bolt head and a collar. The bolt head has a pin portion and a head portion. The pin extends through an end of the pin portion positioned within the bolt so as to couple the bolt head assembly to the bolt. The collar includes a cylindrical body surrounding the pin portion and positioned between the head portion and the bolt. The collar further includes an extractor carried by the collar such that the extractor is non-rotating about the longitudinal axis of the bolt when the bolt mechanism is installed in a firearm and when the bolt and the bolt head rotate together about the longitudinal axis. In one embodiment, the pin includes a first end positioned in a first opening in a sidewall of the bolt, a second end positioned in a second opening in the sidewall of the bolt, and an elongate body positioned in a through-hole in the end of the pin portion.

BRIEF DESCRIPTION OF THE DRAWINGS

Non-limiting and non-exhaustive embodiments are described with reference to the following drawings. The same reference numerals refer to like parts throughout the various views, unless otherwise specified.

FIG. 1 is an isometric view of a firearm with a bolt mechanism in a closed position in accordance with one embodiment.

FIG. 2 is an isometric view of the firearm of FIG. 1 with the bolt mechanism in an open position in accordance with one embodiment.

FIG. 3 is a partial cross-sectional view of the firearm of FIG. 1.

FIG. 4 is a detailed view of the firearm of FIG. 3.

FIG. 5 is an isometric view of a bolt mechanism and a firing pin assembly in accordance with one embodiment.

FIG. 5A is a side view of the firearm of FIG. 1.

FIG. 5B is a cross-sectional view of the firearm of FIG. 5A taken along line 5B-5B.

FIG. 6 is a front view of the bolt mechanism of FIG. 5.

FIG. 7 is a cross-sectional view of a distal portion of the bolt mechanism taken along line 7-7 of FIG. 6.

FIG. 8 is a cross-sectional view of the distal portion of the bolt mechanism taken along line 8-8 of FIG. 6.

FIG. 9 is a detailed view of a joint of the bolt mechanism of FIG. 8.

FIG. 10 is an exploded isometric view of a bolt mechanism and firing pin assembly in accordance with one embodiment.

FIG. 11 is an exploded view of a bolt head assembly in accordance with one embodiment.

FIGS. 12 and 13 are isometric views of an extractor in accordance with one embodiment.

FIG. 14 is an isometric view of a pin in accordance with one embodiment.

FIG. 15 is a site view of a bolt mechanism in accordance with one embodiment.

FIG. 16 is a cross-sectional view of the bolt mechanism taken along line 16-16 of FIG. 15.

FIG. 17 is an exploded view of a bolt head assembly in accordance with one embodiment.

DETAILED DESCRIPTION

The present technology is generally directed to firearms, bolt mechanisms, extractors, and methods of using the same. Specific details of numerous embodiments of the technology are described below with reference to FIGS. 1-17. A person of ordinary skill in the art will understand that the technology can have other embodiments with additional elements and features, or the technology can have other embodiments without several of the features shown and described below with reference to FIGS. 1-17. The terms “proximal” and “distal” are used to describe the illustrated embodiments and are used consistently with the description of non-limiting exemplary applications. The terms proximal and distally are used in reference to the user's body when the user fires a firearm, unless the context clearly indicates otherwise.

FIGS. 1 and 2 are isometric views of a firearm 100 in accordance with one embodiment. The firearm 100 can include a bolt mechanism 110, a barrel 120, a main body or receiver assembly 130, a grip 136, and a stock 138. The bolt mechanism 110 can receive and hold a shell (or case) of a cartridge. After firing the projectile, the bolt mechanism 110 can be moved from a locked or closed position (FIG. 1) to the open position (FIG. 2) to eject the empty shell. For example, a handle 160 can be rotated to unlock the bolt mechanism 110, and the bolt mechanism 110 can be slid proximally to extract the empty shell from the firearm 100 through an ejection port 158 (FIG. 2).

FIG. 3 is a partial cross-sectional view of the firearm 100 with the bolt mechanism 110 in the closed position. FIG. 4 is a detailed cross-sectional view of a portion of the firearm 100. Referring to FIG. 4, the bolt mechanism 110 can include a bolt 180 and a bolt head assembly 190. The bolt head assembly 190 can move to, for example, maintain contact between a bolt head 193 and the barrel 120. For example, an extractor of the bolt head assembly 190 can apply forces to other components of the bolt head assembly 190 to allow floating of the bolt head 193 such that contact is maintained between a bearing surface 191 of the bolt head 193 (e.g., a surface of a bolt lug 195) and a bearing member 197. The bearing member 197 can be a barrel extender. A back surface 199 of the bolt head 193 can bear against a shoulder 201. As a result, the bearing surface 191 can lay flat against the surface of the bearing member 197 and the back surface 199 can lay flat against the surface of the shoulder 201 to omit, inhibit, or substantially eliminate high stresses between the bolt head assembly 190 and the adjacent components, as well as maintaining alignment of the bolt head 193 throughout firing.

FIG. 5 is an isometric view of a firing pin assembly 170 positioned within the bolt mechanism 110. FIG. 5A is a side view of the firearm 100 with the bolt mechanism. FIG. 5B is a cross-sectional view of the firearm of FIG. 5A taken along line 5B-5B. Referring to FIG. 5, the bolt 180 can include a tubular main body 181 and the handle 182 with a knob 184. The handle 182 can be used to rotate lugs 313a, 313b (FIG. 6) from unlocked positions to locked positions.

FIG. 6 is a front view of the bolt mechanism 110. FIG. 7 is a cross-sectional view of a distal portion of the bolt mechanism 110 taken along line 7-7 of FIG. 6. FIG. 8 is a cross-sectional view of the distal portion of the bolt mechanism 110 taken along line 8-8 of FIG. 6. Referring to FIGS. 5 and 7, the bolt head assembly 190 can further include an extractor assembly 310 and a pin 352 (FIG. 7). The extractor assembly 310 can include an extractor 322 and a collar 324 that cooperate to react substantially all applied loads associated with the extractor 322 within the bolt head assembly 190 to allow rotation of the bolt head 193. Thus, the bolt head 193 is a floating bolt head. For example, the forces applied by the extractor 322 can be reacted by the collar 324, or other component of the bolt head assembly 190. As such, the bolt 180 does not react applied forces associated with the extractor 322, such that bolt head 193 can freely rotate relative to the bolt 180. While the bolt head 193 rotates, the extractor 322 can remain spaced apart from the bolt 180 and positioned in a feature 189 of FIG. 5B (e.g., a channel or a slot) extending longitudinally along the firearm 100. As such, the extractor 322 can be substantially non-rotating about a longitudinal axis 211 (FIG. 5) of the bolt 180. As the bolt 180 rotates about its longitudinal axis 211, the firearm 100 can maintain the angular position of the extractor 322. The firearm 110 can constrain the extractor 322 to prevent rotation of the extractor about the longitudinal axis 211. When the bolt mechanism 110 is uninstalled, the extractor 322 can the bolt 180 can rotate together. When the bolt mechanism 110 is installed in the firearm 100, the extractor 322 is non-rotatable the longitudinal axis 211 because the firearm 100 constrains the extractor 322.

In some embodiments, including the illustrated embodiment, bolt head 193 can freely rotate about the two axes of rotation 192, 194 (FIG. 5). When the bolt head 193 is in a maximum rotated position relative to the transverse axis of rotation 194 of FIG. 5, a longitudinal axis 337 of the bolt head 193 can define an angle of rotation α of FIG. 7. (FIG. 7 shows the bolt head 193 in an unrotated or central position) When the bolt head 193 is in a maximum rotated position relative to the transverse axis of rotation 192 of FIG. 5, the longitudinal axis 337 can define an angle θ of FIG. 8. (FIG. 8 shows the bolt head 193 in the unrotated or central position) In some embodiments, the angles θ, α can be equal to or less than about 5 degrees, 3 degrees, 2 degrees, or 1.5 degrees. In one embodiment, one or both angles θ, α can be equal to or less than about 3 degrees. Other angles are also possible.

FIG. 9 is a detailed view of a joint 333 of the bolt mechanism 110. As used herein, the term “joint” is a broad term that includes, but is not limited to, the region of contact between two elements that permits relative movement between the two elements. The term “rotational joint” is a broad term that includes, without limitation, a joint that has at least one rotational degree of freedom with substantially no axial movement in at least one direction. For example, a rotational joint can be in the form of a swivel joint or pivot joint. A pivot joint includes, without limitation, a joint that is generally rotationally unrestrained in at least two rotational degrees of freedom. The joint 333 of FIG. 9 is a pivot joint with two rotational degrees of freedom. The bolt head 193 can include a surface 342 of a pivoting feature 402 that mates with an inner surface 344 of the bolt 180. In some embodiments, the surface 342 is a curved surface, such as a partially spherical surface with a radius curvature selected based on the desired movement (e.g., pivoting, rolling, sliding, etc.) along the surface 344 of the bolt 180.

Referring to FIGS. 5 and 7, a pin 320 can limit or prevent axial movement of the bolt head 193. A gap 359 (FIG. 7) between the pin 320 and bolt head 193 can allow rotation of the bolt head 193. The extractor 322 can include a biasing member 327 and a claw portion 329. The biasing member 327 can urge the extractor 322 towards an engagement position for receiving a rim of cartridge shell in a slot 365 (FIG. 7). As shown in FIG. 7, the biasing member 327′ can contact a protrusion or mounting portion 364 of the collar 324 to urge the claw portion 329 inwardly towards a firing pin hole 370. A rearward or proximal end 374 of the extractor 322 is spaced apart of an outer surface 376 of the bolt 180. In some embodiments, the extractor proximal end 374 is positioned distal of one or both axes of rotation 192, 194, but the extractor proximal end 374 can be at other locations.

FIG. 10 is an exploded isometric view of the bolt mechanism 110 and the firing pin assembly 170. The firing pin assembly 170 can include a firing pin 200, a firing pin spring 202, a bolt shroud 208, and a cocking piece 210. The cocking piece 210 has a cam member 214, which can be engaged by firing pin cam 208 of the bolt 180. The bolt shroud 208 may also be referred to as a bolt sleeve, and the cocking piece 210 may also be referred to as a striker. The firing pin assembly 170 can be assembled and inserted into a proximal end 230 of the bolt 180. The firing pin assembly 170 can be advance distally through a passageway 231 defined by a sidewall 252 of the bolt 180 to position a tip 232 of the firing pin 200 within the bolt head assembly 190. Other types of firing pin assemblies can be used with the bolt mechanism 110.

The bolt head 193 can include a pin portion 330, a head portion 332, and lugs 333a, 333b. The lugs 333a, 333b can be used to lock the bolt mechanism 110 to the receiver, or other component of the firearm. The pin portion 330 can be inserted through the collar 324 and into a distal portion of the passageway 231. The configuration and features of the bolt head 193 can be selected based on, for example, the desired motion of the bolt head 193.

FIG. 11 is an exploded isometric view of the bolt head assembly 190. The pin portion 330 includes a through hole 440 and a pivoting feature 402. The pivoting feature 402 extends circumferentially between an ends 410, 412 (see FIG. 7) of the through hole 440. The pin 352 can be positioned in the opening 470 to rotatably couple the extractor 322 to the collar 324. The biasing member 327 can engage the outer surface of the mounting portion 364 and can extend generally longitudinally along the bolt mechanism 110.

FIGS. 12 and 13 are isometric views of the extractor 322 including a claw portion 329 and a main body 534. The claw portion 329 can include projections 500, 502 in the form of arcuate lips that define a channel 510 for receiving a rim of a shell. When the extractor 322 is pulled proximally, the projection 500 can pull the empty shell out of the firing chamber. The claw portion 329 can have other features and configurations. The main body 534 can include two elongated slots 540, 542 (e.g., slots formed by a cutting process) that define the biasing member 327, which can be a cantilevered member with a mounting end 550 (FIG. 13) connected to the claw portion 329. An elongated body 560 of the biasing member 327 can extend generally longitudinally along the bolt mechanism 110, but the elongated body 560 can be at other orientations. The extractor 322 can be made, in whole or in part, of metal (e.g., steel, aluminum, etc.), plastic, or the like.

Referring to FIGS. 11-13, the mounting portion 364 of the collar 324 can be positioned between mounting portions 480, 482 of the extractor 322. The pin 352 can be inserted through openings 600, 470, 602 to define an axis of rotation 642 (FIG. 5) about which the extractor 322 rotates. When the claw portion 329 is moved away from the bolt head 193, the biasing member 327 can be pressed against the portion 364 to urge the extractor 322 back towards the bolt head 193. Both the pin 352 and collar 324 can be non-rotating about the longitudinal axis of the bolt 180 when installed in the firearm.

FIG. 14 is an isometric view of the pin 320 including heads 630, 632 and a main body 634. A pivoting feature 640 is positioned along the main body 634. A through hole 643 can extend transversely through the main body 634. In some embodiments, the pivoting feature 640 can have a partially spherical surface or curved surface suitable for moving (e.g., pivoting, rolling, sliding, etc.) along another surface. In one embodiment, the pivoting feature 640 is a band having a curved surface.

FIG. 15 is a side view of the bolt mechanism 110. FIG. 16 is a cross-sectional view of the bolt mechanism 110 along line 16-16 of FIG. 15. Referring to FIGS. 15 and 16, the through hole 643 (FIG. 16) can be longitudinally aligned with a longitudinal axis 650 (FIG. 15) of the bolt mechanism 110. The firing pin 200 (FIG. 10) can be inserted through the through hole 643 to position the firing pin 200 within the bolt head 193. The heads 630, 632 of the pin 320 can engage the sidewall 252 of the bolt 180.

FIG. 17 is an exploded isometric view of a bolt head assembly 700 in accordance with one embodiment. The bolt head assembly 700 is generally similar to the bolt head assembly 190 discussed in connection with FIGS. 1-16, except as detailed below. The bolt head assembly 700 includes an extractor assembly 710 including a collar 720, a pin 722, a biasing member 723, and an extractor 725. The biasing member 723 can be partially received within an opening 730 of a protrusion or mounting portion 732. In some embodiments, the biasing member 723 can be a helical spring, a coil spring, or other biasing device made of metal, plastic, or other suitable materials capable of urging the extractor 725 towards a distal end of the bolt head 740. The biasing member 723 can be compressed as the extractor claw portion moves away from the bolt head 740. In other embodiments, the extractor assembly 710 can include two springs, each with different spring characteristics. The extract 725 can pivot about the pin 722 without applying forces to the bolt 180.

The embodiments, features, extractors, bolt mechanism, methods and techniques described herein may, in some embodiments, be similar to any one or more of the embodiments, mounting clamps, features, systems, devices, materials, methods and techniques described in U.S. Pat. No. 7,743,543; U.S. Provisional Patent Application No. 61/600,477; and U.S. Provisional Patent Application No. 61/602,520. U.S. Pat. No. 7,743,543, U.S. patent application Ser. No. 13/771,021, and U.S. Provisional Pat. App. Nos. 61/600,477 and 61/602,520 are incorporated herein by reference in their entireties. In addition, the embodiments, features, systems, devices, materials, methods and techniques described herein may, in certain embodiments, be applied to or used in connection with any one or more of the embodiments, features, systems, devices, materials, methods and techniques disclosed in the above-mentioned U.S. Pat. No. 7,743,543; U.S. Provisional Patent Application No. 61/600,477; and U.S. Provisional Patent Application No. 61/602,520. For example, the mounting clamps and this features disclosed in U.S. Pat. No. 7,743,543 may incorporate the embodiments disclosed herein. The bolt mechanisms and other features disclosed herein can be incorporated in into a wide range of different firearms (e.g., rifle, pistol, or other portable guns) to receive cartridges and removing empty cartridge shells.

From the foregoing, it will be appreciated that specific embodiments of the invention have been described herein for purposes of illustration, but well-known structures and functions have not been shown or described in detail to avoid unnecessarily obscuring the description of at least some embodiments of the invention. Where the context permits, singular or plural terms may also include the plural or singular term, respectively. Unless the word “or” is associated with an express clause indicating that the word should be limited to mean only a single item exclusive from the other items in reference to a list of two or more items, then the use of “or” in such a list shall be interpreted as including (a) any single item in the list, (b) all of the items in the list, or (c) any combination of the items in the list. The singular forms “a,” “an,” and “the” include plural referents unless the context clearly indicates otherwise. Thus, for example, reference to “a lug” refers to one or more lugs, such as two or more lugs, three or more lugs, or four or more lugs.

These and other changes can be made to the embodiments in light of the above-detailed description. In general, in the following claims, the terms used should not be construed to limit the claims to the specific embodiments disclosed in the specification and the claims, but should be construed to include all possible embodiments along with the full scope of equivalents to which such claims are entitled. Accordingly, the claims are not limited by the disclosure.

Claims

1. A bolt mechanism, comprising: a bolt configured to receive a firing pin assembly and having a longitudinal axis;a pin; anda bolt head assembly including a bolt head having a pin portion and a head portion, wherein the pin extends through an end of the pin portion positioned within the bolt so as to couple the bolt head assembly to the bolt,a collar including a cylindrical body, wherein the cylindrical body surrounds the pin portion and is positioned between the head portion and the bolt, andan extractor carried by the collar such that the extractor is non-rotating about the longitudinal axis of the bolt when the bolt mechanism is installed in a firearm and when the bolt and the bolt head rotate together about the longitudinal axis.

2. The bolt mechanism of claim 1, further comprising a handle, and wherein the collar is rotationally fixed relative to the longitudinal axis when the bolt mechanism is installed in the firearm such that the bolt and the bolt head rotate relative to the collar when the handle of the bolt mechanism is rotated to operate the bolt mechanism.

3. The bolt mechanism of claim 1, wherein the pin includes a first end positioned in a first opening in a sidewall of the bolt,a second end positioned in a second opening in the sidewall of the bolt, andan elongate body positioned in a through-hole in the end of the pin portion.

4. The bolt mechanism of claim 1, wherein an axial length of the bolt head is shorter than an axial length of the bolt, and wherein an entire length of a section of the pin portion protruding from the collar is located within the bolt.

5. The bolt mechanism of claim 1, wherein the cylindrical body has an inner surface that extends continuously about an entire circumference of a section of the pin portion located between the bolt and the bolt head.

6. The bolt mechanism of claim 1, wherein the pin portion is dimensioned to be inserted through an opening defined by the cylindrical body and inserted into an end of the bolt.

7. The bolt mechanism of claim 1, wherein the extractor includes a body and a claw portion, wherein the body of the extractor is coupled to the collar, and wherein the claw portion is positioned to engage a case of a cartridge during use.

8. The bolt mechanism of claim 7, wherein the extractor urges the claw portion towards a firing pin hole of the bolt head when the bolt mechanism is installed in the firearm.

9. The bolt mechanism of claim 1, wherein the bolt head includes a lug that engages a receiver of the firearm for firing the firearm when the bolt mechanism is in a locked configuration, and wherein the lug allows an empty cartridge shell held by the extractor to be pulled along a bore of the receiver by operating the bolt mechanism.

10. The bolt mechanism of claim 1, wherein the extractor has a lug-receiving gap and a claw, and wherein the bolt head is rotatable relative to the extractor to move a lug of the bolt head into the lug-receiving gap to unlock the bolt mechanism and out of the lug-receiving gap to lock the bolt mechanism.

11. The bolt mechanism of claim 1, wherein the pin substantially prevents rotation of the bolt head relative to the bolt about the longitudinal axis of the bolt.

12. A bolt mechanism for a firearm, comprising: a bolt;a pin; anda bolt head assembly including a bolt head coupled to the bolt by the pin and including a head portion,an extractor, anda collar configured to carry the extractor and including a cylindrical body positioned between the head portion and the bolt, wherein the bolt head extends through the cylindrical body and into the bolt such that the bolt and the bolt head rotate relative to the collar and the extractor when the bolt mechanism is installed in the firearm.

13. The bolt mechanism of claim 12, wherein the pin rotationally fixes the bolt head to the bolt such that the bolt head and the bolt rotate together about a longitudinal axis of the bolt.

14. The bolt mechanism of claim 12, wherein the bolt and the bolt head are configured to rotate relative to the collar when the collar is rotationally fixed relative to the receiver of the firearm and when the bolt mechanism is moved between a locked configuration and an unlocked configuration.

15. The bolt mechanism of claim 12, wherein the extractor is non-rotating about a longitudinal axis of the bolt head when the bolt mechanism is installed in the firearm and when the bolt head rotates about the longitudinal axis by operating the bolt mechanism.

16. The bolt mechanism of claim 12, wherein the bolt head includes a pin portion extending through the cylindrical body and into a bore of the bolt, and wherein the pin extends through a sidewall of the bolt and an end region of the pin portion located along the bore.

17. The bolt mechanism of claim 12, wherein the cylindrical body has a transverse cross section with a continuous perimeter about a circumference of the bolt head.

18. A bolt mechanism for a firearm, comprising: a bolt;a bolt head assembly including a bolt head movably coupled to the bolt,a collar with a cylindrical body positioned between a portion of the bolt and a portion of the bolt head, anda claw extractor configured to hold a cartridge case and carried by the collar, wherein the bolt and the bolt head assembly are rotatable relative to the collar and the claw extractor when the bolt mechanism is installed in the firearm; anda pin coupling the bolt head assembly to the bolt.

19. The bolt mechanism of claim 18, wherein the cylindrical body has a transverse cross section that is ring shaped with a continuous closed outer perimeter.

20. The bolt mechanism of claim 18, wherein the bolt and the bolt head are configured to rotate relative to the collar when the collar is rotationally fixed relative to the receiver of the firearm and the bolt mechanism is moved between a locked configuration and an unlocked configuration.

21. The bolt mechanism of claim 18, wherein the extractor is non-rotating about a longitudinal axis of the bolt when the bolt mechanism is installed in the firearm and when the bolt head rotates about the longitudinal axis.

22. The bolt mechanism of claim 18, wherein the bolt and the bolt head are configured to rotate relative to the collar when a receiver of the firearm prevents rotation of the collar and the bolt mechanism is moved between a locked configuration and an unlocked configuration.

23. The bolt mechanism of claim 18, wherein the extractor is non-rotating about a longitudinal axis of the bolt when the bolt mechanism is installed in the firearm and when the bolt head rotates about the longitudinal axis.

24. The bolt mechanism of claim 18, wherein the cylindrical body has a solid circular transverse cross section.

25. A bolt mechanism for a firearm, comprising: a bolt; anda bolt head assembly including a bolt head,a collar with a cylindrical body positioned between a portion of the bolt and a portion of the bolt head, anda claw extractor configured to hold a cartridge case and carried by the collar, wherein the bolt and the bolt head assembly are rotatable relative to the collar and the claw extractor when the bolt mechanism is installed in the firearm, and wherein the bolt head is received by the bolt, and wherein the collar surrounds the bolt head.

26. A bolt mechanism for a firearm, comprising: a bolt;a bolt head assembly including a bolt head,a collar with a cylindrical body positioned between a portion of the bolt and a portion of the bolt head, anda claw extractor configured to hold a cartridge case and carried by the collar, wherein the bolt and the bolt head assembly are rotatable relative to the collar and the claw extractor when the bolt mechanism is installed in the firearm; anda pin extending through the bolt and the bolt head such that the bolt and the bolt head rotate together about a longitudinal axis of the bolt.

27. A bolt mechanism for a firearm, comprising: a bolt;a bolt head assembly including a bolt head,a collar with a cylindrical body positioned between a portion of the bolt and a portion of the bolt head, anda claw extractor configured to hold a cartridge case and carried by the collar, wherein the bolt and the bolt head assembly are rotatable relative to the collar and the claw extractor when the bolt mechanism is installed in the firearm; anda pin that extends transversely through the bolt head and the bolt.

28. A bolt mechanism for a firearm, comprising: a bolt; anda bolt head assembly including a bolt head,a collar with a cylindrical body positioned between a portion of the bolt and a portion of the bolt head, anda claw extractor configured to hold a cartridge case and carried by the collar, wherein the bolt and the bolt head assembly are rotatable relative to the collar and the claw extractor when the bolt mechanism is installed in the firearm,wherein the bolt head includes a pin portion extending through the cylindrical body and into a bore of the bolt, and wherein a pin extends through a sidewall of the bolt and an end region of the pin portion located within the bore.

29. A bolt mechanism for a firearm, comprising: a bolt; anda bolt head assembly including a bolt head,a collar with a cylindrical body positioned between a portion of the bolt and a portion of the bolt head, anda claw extractor configured to hold a cartridge case and carried by the collar, wherein the bolt and the bolt head assembly are rotatable relative to the collar and the claw extractor when the bolt mechanism is installed in the firearm,wherein the bolt head includes a pin portion extending through the cylindrical body and into a bore of the bolt, and wherein a pin extends through a sidewall of the bolt and an end region of the pin portion located within the bore.

30. A bolt mechanism, comprising: a bolt;a bolt head assembly including a bolt head movable relative to the bolt, the bolt head including a head portion,an extractor, anda collar configured to carry the extractor, wherein the bolt and the bolt head are rotatable relative to the collar and the extractor when the bolt mechanism is installed in a firearm; anda pin coupling the bolt head assembly to the bolt.

31. The bolt mechanism of claim 30, wherein the bolt head is rotatably coupled to the bolt.

32. The bolt mechanism of claim 30, wherein the collar is positioned between the head portion and the bolt.