Patent Application
20240255247
Not applicable to this application.
The present disclosure relates generally to throat inserts for barrels of firearms, including rifles, pistols, shotguns, tank barrels, artillery barrels, and the like.
Not applicable to this application.
A conventional firearm barrel is an elongated single piece of metal with a chamber that receives the ammunition cartridge and a bore that receives the bullet (or round) fired from the ammunition cartridge. The barrel of a firearm typically receives wear during use, and may become worn or damaged after repeated firings. After repeated usage, for example, the rifling in the bore of a rifle may become worn and diminished thereby reducing the accuracy of the rifle. In addition, cracks, pits and fissures can develop within the bore, particularly within the portion of the bore that is nearest to the chamber that holds the ammunition cartridge during firing of the firearm where the heat and pressure are the most intense. A worn barrel may be replaced or repaired, however, such activities require time and expense, and result in periods of inaction of the firearm while the firearm is being repaired or replace. Accordingly, techniques and technologies that reduce barrel wear, and that at least partially mitigate the expense and inconvenience associated with barrel repair or replacement, would have considerable utility.
Some of the various embodiments of the present disclosure relate to a throat inserts for barrels of firearms, including rifles, pistols, shotguns, tank barrels, artillery barrels, and the like.
For example, in some embodiments, an assembly (e.g. a firearm) includes a barrel having a throat end positionable proximate to a chamber, a throat region disposed within the throat end of the barrel, and a bore extending away from the throat region to a muzzle end of the barrel spaced apart from the throat end, the bore being configured to allow a bullet from an ammunition cartridge disposed within the chamber to pass through the bore and to exit from the bore through a discharge opening proximate the muzzle end. The assembly further includes a throat insert disposed within the throat region of the barrel, the throat insert including an insert passage substantially aligned with the bore, the insert passage being configured to allow the bullet from the ammunition cartridge to pass through the insert passage and into the bore, the throat insert being formed of a different material than the barrel. More specifically, in some embodiments, the barrel is formed of a first material (e.g. steel), and the throat insert is formed of a second material (e.g. brass, titanium, etc.) that is at least one of harder or more durable than the first material.
In some other embodiments, a chamber body is coupled to the throat end of the barrel, the chamber body having the chamber formed therein, the chamber being configured to securely position the ammunition cartridge during firing of the ammunition cartridge, the chamber having an exit opening aligned with the insert passage of the throat insert.
In further embodiments, a firearm assembly (e.g. firearm) includes a chamber configured to securely position an ammunition cartridge, the chamber having an exit opening configured to allow a bullet from the ammunition cartridge disposed within the chamber to pass through the exit opening; a barrel having a throat end proximate to the chamber, a throat region disposed within the throat end, and a bore extending away from the throat region to a muzzle end of the barrel spaced apart from the throat end, the bore being configured to allow the bullet from the ammunition cartridge disposed within the chamber to pass through the bore and to exit from the bore through a discharge opening proximate the muzzle end. The assembly further includes a throat insert disposed within the throat region of the barrel, the throat insert including an insert passage substantially aligned with the exit opening of the chamber and substantially aligned with the bore, the insert passage being configured to allow the bullet from the ammunition cartridge to pass through the insert passage and into the bore, the throat insert being formed of a different material than the barrel. For example, in some embodiments, the barrel comprises an elongated cylindrical barrel formed of a first material, and the throat insert comprises a cylindrical throat insert formed of a second material, the second material being at least one of harder or more durable than the first material.
In still further embodiments, the firearm assembly may further include a chamber body coupled to the throat end of the barrel, the chamber body having the chamber formed therein. In some embodiments, the chamber body includes a first ring groove formed therein and disposed about the exit opening, and the barrel further includes a second ring groove formed therein and disposed about an entrance to the insert passage. The firearm assembly may further comprise a pressure ring disposed at least partially within the first ring groove and at least partially within the second ring groove, the pressure ring being fittingly engaged between the chamber body and the barrel to substantially prevent a pressure release within at least one of the insert passage and the chamber during firing of the ammunition cartridge. In some embodiments, the pressure ring fittingly engages a portion of the throat insert.
There has thus been outlined, rather broadly, some of the embodiments of the present disclosure in order that the detailed description thereof may be better understood, and in order that the present contribution to the art may be better appreciated. There are additional embodiments that will be described hereinafter and that will form the subject matter of the claims appended hereto. In this respect, before explaining at least one embodiment in detail, it is to be understood that the various embodiments are not limited in its application to the details of construction or to the arrangements of the components set forth in the following description or illustrated in the drawings. Also, it is to be understood that the phraseology and terminology employed herein are for the purpose of the description and should not be regarded as limiting.
To better understand the nature and advantages of the present disclosure, reference should be made to the following description and the accompanying figures. It is to be understood, however, that each of the figures is provided for the purpose of illustration only and is not intended as a definition of the limits of the scope of the present disclosure. Also, as a general rule, and unless it is evidence to the contrary from the description, where elements in different figures use identical reference numbers, the elements are generally either identical or at least similar in function or purpose.
Various other objects, features and attendant advantages of the present invention will become fully appreciated as the same becomes better understood when considered in con-junction with the accompanying drawings, in which like reference characters designate the same or similar parts throughout the several views, and wherein:
Some of the various embodiments of the present disclosure relates generally to throat inserts for barrels of firearms, including rifles, pistols, shotguns, tank barrels, artillery barrels, and the like. For example, in some embodiments, a barrel of a firearm includes a bore having a throat region that is proximate a chamber that receives an ammunition cartridge, and a throat insert positioned within the throat region. The throat insert may be fabricated of a harder, more durable material than the metal that is used for the barrel, and may be press fit or otherwise installed into the throat region of the barrel.
During operation of the firearm, as ammunition cartridges are fired, the bullet (or round) traverses through the throat insert and out through the bore of the barrel. Because the throat insert is positioned proximate to the chamber that contains the ammunition cartridge, the throat insert is exposed to the most severe environment during firing of the ammunition cartridge. Specifically, the throat insert may experience a severe environment that may include intense heating and pressurization, along with hot particulates, powder, sparks, and burning gases. In some embodiments, due to appropriate selection of materials for the throat insert, the throat insert is better able to withstand the extreme heating and pressurization from the firing of the ammunition cartridge, thereby reducing the wear and damage on the barrel and extending the useful life of the barrel. In at least some embodiments, the throat insert may be replaceable within the throat of the barrel without requiring a full replacement of the barrel. Accordingly, throat inserts for barrels of firearms and the like may advantageously reduce barrel wear, and may considerably mitigate the expense and inconvenience associated with barrel repair or replacement.
The following detailed description of example embodiments refers to the accompanying drawings. The same reference numbers in different drawings may be used to identify the same or similar elements.
As best shown in
As described more fully below, a throat insert 60 is positioned within a throat region 70 of the bore 33 that lies within the throat end 31 of the barrel 30 proximate to the chamber body 20. In some embodiments, the throat region 70 is a portion of the bore 33 within the throat end 31 of the barrel 30 that is proximate to (or adjacent to) the chamber 24 of the chamber body 20 that receives the ammunition cartridge 19. Because the throat insert 60 is positioned within the throat region 70 of the bore 33 proximate to the chamber 24 that contains the ammunition cartridge 19, the throat insert 60 is exposed to the most extreme heating and pressurization during firing of the ammunition cartridge 19. Thus, rather than the barrel 30 experiencing these extreme temperatures and pressures associated with firing, the more durable throat insert 60 bears the brunt of these extreme conditions.
Therefore, in some embodiments, an assembly (e.g. firearm 10 as shown in
In some embodiments, a chamber body 20 is coupled to the throat end 31 of the barrel 30, the chamber body 20 having the chamber 24 formed therein, the chamber 24 being configured to securely position the ammunition cartridge 19 during firing of the ammunition cartridge 19, the chamber 24 having an exit opening aligned with the insert passage 63 of the throat insert 60. In further embodiments, a receiver 14 is operatively coupled to the chamber body 20, the receiver 14 adapted to receive the ammunition cartridge 19 and to position the ammunition cartridge 19 into the chamber 24 of the chamber body 20. In some embodiments, a stock 12 is coupled to at least one of the receiver 12, the chamber body 20, or the barrel 30.
As best shown in
It will be appreciated that the barrel 30 may have various lengths used for various types of firearms such as rifles, pistols, shotguns, or other larger guns (e.g. artillery). The barrel 30 is preferably constructed of a unitary piece of metal, but various other types of suitable materials may be utilized to construct the barrel 30. The outer surface of the barrel 30 may have various cross sectional shapes, but it is preferable that the bore 30 of the barrel 30 has a circular cross sectional shape.
As further shown in
It will be appreciated that, in at least some embodiments, the throat insert 60 may be fabricated of a harder, more durable material than the metal that is used for the barrel 30. For example, in some embodiments, the throat insert 60 may be formed from brass, however, in alternate embodiments, the throat insert 60 may be fabricated using titanium, tungsten, chromium, hardened steel, or any other suitable alloys or materials. In some embodiments, the insert passage 63 may have a relatively smooth wall surface (i.e. no rifling). In some alternate embodiments, however, the insert passage 63 may include rifling 65 (helical lands and grooves, shown in dashed lines in
During operation of the firearm, as ammunition cartridges are fired, the bullet (or round) traverses through the throat insert 60 and out through the bore 33 of the barrel 30. More specifically, the bullet fired from the ammunition cartridge 19 enters the entrance opening 62 of the throat insert 60, passes through the insert passage 63 and through the exit 64, passing into the bore 33 of the barrel 30 and ultimately exiting from the discharge opening 34 at the muzzle end 35 of the barrel 30.
Accordingly, in some embodiments the barrel 30 comprises an elongated cylindrical barrel (
As noted above, as the ammunition cartridge 19 is fired, the bullet (or round) traverses through the throat insert 60 and out through the bore 33 of the barrel 30. More specifically, the bullet fired from the ammunition cartridge 19 enters the entrance opening 62 of the throat insert 60, passes through the insert passage 63 and through the exit 64, passing into the bore 33 of the barrel 30 and ultimately exiting from the discharge opening 34 at the muzzle end 35 of the barrel 30.
Because the throat insert 60 is positioned proximate to the chamber 24 that contains the ammunition cartridge 19, the throat insert 60 is exposed to the most extreme environment during firing of the ammunition cartridge 19. In some embodiments, due to appropriate selection of materials for the throat insert 60, the throat insert 60 may be better able to withstand the extreme heating, pressurization, and other environmental conditions resulting from the firing of the ammunition cartridge 19, thereby reducing the wear and damage on the barrel 30 and extending the useful life of the barrel 30. In at least some embodiments, the throat insert 60 may be replaceable within the throat region 70 of the barrel 30 without requiring a full replacement of the barrel 30. Accordingly, throat inserts for barrels of firearms and the like may advantageously reduce barrel wear, and may considerably mitigate the expense and inconvenience associated with barrel repair or replacement.
In at least some embodiments, the chamber body 20 has an elongated structure with a concentric longitudinal axis. The external cross-sectional shape of the chamber body 20 is preferably circular as best illustrated in
The first end 22 of the chamber body 20 includes a first connector 15 that is adapted to be removably connected to the receiver 14 of the firearm 10 thereby allowing the interchangeability of the chamber body 20 with respect to the receiver 12 of the firearm 10. It will be appreciated that the first connector 15 may include any connector device suitable for securely attaching the chamber body 20 in a non-movable manner to the receiver 14 of the firearm to prevent movement during firing of the firearm and that also allows for releasing of the chamber body 20 from the receiver 14 when the user desires to change the chamber body 20 on the firearm 10.
In some embodiments, the first connector 15 is comprised of a threaded structure that threadably connects to a corresponding threaded structure on the receiver 14. For example, in the embodiment shown in
The second end 26 of the chamber body 20 includes a second connector 17 that is adapted to be removably connected to an inner connector 79 of the throat end 31 of the barrel 30. It will be appreciated that the second connector 17 may include any connector device suitable for securely attaching the barrel 30 in a non-movable manner to the chamber body 20 to prevent movement during firing of the firearm 10 and that also allows for releasing of the barrel 30 from the chamber body 20 when the user desires to change the barrel 30 on the firearm 10.
For example, as shown in
In some embodiments, the chamber body 20 may include a plurality of gripping members 21 for selective engagement by a tool such as, but not limited to, a spanner wrench. Various other structures may be used on the chamber body 20 to allow for tightening and removal of the chamber body 20 with respect to the receiver 14 of the firearm 10.
In some embodiments, the chamber body 20 may be constructed of a first unitary piece of metal and the barrel 30 may be constructed of a second unitary piece of metal that is manufactured separate of the first unitary piece of metal. In some embodiments, the chamber body 20 and the barrel 30 may be manufactured using a CNC machine to assist in reducing manufacturing costs.
An alternate embodiment is shown in
Similarly, the throat end 31 of the barrel 30 includes a ring groove 42 that is sized and positioned to receive the other end of pressure ring 40 when the chamber body 20 and barrel 30 are secured, as best shown in
Like ring groove 41, ring groove 42 may be annular and concentric with the bore 33 of the barrel 30. Also, ring groove 42 includes a sealing surface 44 that makes contact with the pressure ring 40 when the barrel and the chamber body are assembled. The sealing surface 44 may be substantially planar and parallel to the end face of barrel 30, as shown in
The pressure ring 40 may be comprised of brass or any other suitable material that is capable of withstanding the temperatures and pressures present when a gun is fired and of forming a good seal. Modern rifle cartridges may create pressures exceeding 50,000 or 60,000 psi, and for certain uses, ammunition in the future is expected to create even greater pressures, such as 100,000 psi or more. In at least some embodiments, the chamber/barrel system disclosed here can withstand such pressures, and has in testing withstood more than 120,000 psi in a blast lab without failure, leaks, or even any damage to the barrel 30, chamber body 20, or pressure ring 40.
As shown in
In some embodiments, depending upon the particular dimensions of the pressure ring 40 and grooves 41, 42, when the barrel 30 and chamber body 20 are secured together, there may be a slight gap 45 between their end surfaces, as shown in
In an example embodiment, the chamber body 20 and the barrel 30 are reusable, and the pressure ring 40 is relatively inexpensive and replaceable. When the chamber body 20 and the barrel 30 are assembled or reassembled for any reason, a user can install a new pressure ring 40 if needed. As shown in
It is possible to use the same size pressure ring 40 for other chamber bodies and barrels in different calibers, so that one or a few different pressure ring sizes can be kept in stock and used for different barrel/chamber caliber combinations. Of course, it is also possible to use different pressure ring sizes as appropriate or desired for smaller or larger caliber components.
In an example embodiment, a pressure ring 40 can be positioned in channels or grooves 41, 42 in the adjacent ends of the chamber body 20 and the barrel 30, respectively, to create a tight seal between the components and to prevent or reduce wear or damage to the barrel 30 or chamber body 20 during assembly or disassembly. In some embodiments, the pressure ring 40 may be compressed within the grooves 41, 42 when the barrel 30 and chamber body 20 are screwed together.
It will be appreciated that, in some embodiments, the pressure ring 40 may fittingly engage around an end of the throat insert 60 as the throat insert 60 is seated in the throat region 70 of the bore 33 of the barrel 30. For example,
As best shown in
It can be appreciated that the first opening 25 may be part of the chamber 24 to provide a consistent diameter from the first opening 25 to the body portion of the chamber 24 as illustrated in
The inner connector 79 may be comprised of any connector device suitable for securely attaching the barrel 30 in a non-movable manner to the chamber body 20 to prevent movement during firing of the firearm 10 and that also allows for releasing of the barrel 30 from the chamber body 20 when the user desires to change the barrel 30 on the firearm 10.
In some embodiments, the inner connector 79 includes a threaded structure 32 that threadably connects to a corresponding threaded structure (or interior threading) 29 of the second connector 17 of the chamber body 20. More specifically, in some embodiments, the inner connector 79 is comprised of outer threading 32 surrounding at least a portion of the throat end 31 of the barrel 30 that is adapted to threadably connect through the second opening 28 with corresponding interior threading 29 of the second connector 17 of the chamber body 20. It can be appreciated that, in alternate embodiments, the second end 26 of the chamber body 20 may have exterior threading and the inner connector 79 for the throat end 31 of the barrel 30 may include an interiorly threaded opening extending into the throat end 31 of the barrel 30 that threadably connects to such exterior threading.
Accordingly, in some embodiments, a firearm assembly (e.g. firearm 10) includes a chamber 24 configured to securely position an ammunition cartridge 19, the chamber 24 having an exit opening configured to allow a bullet from the ammunition cartridge 19 disposed within the chamber 24 to pass through the exit opening; a barrel 30 having a throat end 31 proximate to the chamber 24, a throat region 70 disposed within the throat end 31 of the barrel 30, and a bore 33 extending away from the throat region 70 to a muzzle end 34 of the barrel 30 spaced apart from the throat end 31, the bore 33 being configured to allow the bullet from the ammunition cartridge 19 disposed within the chamber 24 to pass through the bore 33 and to exit from the bore 33 through a discharge opening 35 proximate the muzzle end 34; and a throat insert 60 disposed within the throat region 70 of the barrel 30, the throat insert 60 including an insert passage 63 substantially aligned with the exit opening of the chamber 24 and substantially aligned with the bore 33, the insert passage 63 being configured to allow the bullet from the ammunition cartridge 19 to pass through the insert passage 63 and into the bore 33, the throat insert 60 being formed of a different material than the barrel 30. For example, in some embodiments, the barrel 30 comprises an elongated cylindrical barrel 30 formed of a first material, and the throat insert 60 comprises a cylindrical throat insert 60 formed of a second material, the second material being at least one of harder or more durable than the first material.
In at least some embodiments, the firearm 10 may further include a chamber body 20 coupled to the throat end 31 of the barrel 30, the chamber body 20 having the chamber 24 formed therein. In further embodiments, the chamber body 20 includes a first ring groove 41 formed therein and disposed about the exit opening, and the barrel 30 further includes a second ring groove 42 formed therein and disposed about an entrance 62 to the insert passage 63, and wherein the firearm 10 further comprises a pressure ring 40 disposed at least partially within the first ring groove 41 and at least partially within the second ring groove 42, the pressure ring 40 being fittingly engaged between the chamber body 20 and the barrel 30 to substantially prevent a pressure release within at least one of the insert passage 63 and the chamber 24 during firing of the ammunition cartridge 19. In some embodiments, the pressure ring 40 fittingly engages a portion of the throat insert 60.
Accordingly, during operation of the firearm, as ammunition cartridges are fired (e.g. by pulling a trigger or actuating a suitable mechanism), the bullet (or round) traverses through the throat insert 60 and out through the bore 33 of the barrel 30. Because the throat insert 60 is positioned proximate to the chamber 24 that contains the ammunition cartridge 19, during firing of the ammunition cartridge 19, the throat insert 60 is exposed to the most severe environment, which may include intense heating and pressurization, and exposure to hot particulates, powder, sparks, and burning gases. Through appropriate selection of materials for the throat insert 60, in at least some embodiments, the throat insert 60 is better able to withstand the extreme environment resulting from the firing of the ammunition cartridge 19, thereby reducing the wear and damage on the barrel 30 and extending the useful life of the barrel 30. In at least some embodiments, the throat insert 60 may be replaceable within the throat region 70 of the bore 33 of the barrel 30 without requiring a full replacement of the barrel 30, thereby mitigating the expense and inconvenience associated with barrel 30 repair or replacement. In some embodiments, the throat insert 60 may be relatively inexpensive and replaceable, such that when the chamber body 20 and the barrel 30 are assembled or reassembled for any reason, a user can install a new throat insert 60 if needed.
In at least some embodiments, the chamber body 20 and the barrel 30 of the firearm 10 may be readily interchangeable, wherein the chamber body 20 provides a chamber 24 that is removably connectable to a receiver 14 of a firearm and an interchangeable barrel 30 that is removably connected to the chamber body 20 opposite of the receiver 14. The chamber body 20, and/or the barrel 30, and/or the throat insert 60 may be changed on the firearm 10 at any time based on the preference of the end user.
Therefore, in some embodiments, a firearm assembly (e.g. firearm 10) includes a stock 12; a receiver 14 coupled to the stock 12, the receiver 14 configured to receive an ammunition cartridge 19; a chamber body 20 coupled to the receiver 14, the chamber body 20 having a chamber 24 configured to receive the ammunition cartridge 19 from the receiver 14 and to securely position the ammunition cartridge 19 for firing, the chamber 24 having an exit opening configured to allow a bullet from the ammunition cartridge 19 disposed within the chamber 24 to pass through the exit opening; a barrel 30 having a throat end 31 coupled to the chamber body 20, a throat region 70 disposed within the throat end 31 of the barrel 30, and a bore 33 extending away from the throat region 70 to a muzzle end 34 of the barrel 30 spaced apart from the throat end 31, the bore 33 being configured to allow the bullet from the ammunition cartridge 19 disposed within the chamber 24 to pass through the bore 33 and to exit from the bore 33 through a discharge opening 35 proximate the muzzle end 34; and a throat insert 60 disposed within the throat region 70 of the barrel 30, the throat insert 60 including an insert passage 63 substantially aligned with the exit opening of the chamber 24 and substantially aligned with the bore 33 of the barrel 30, the insert passage 63 being configured to allow the bullet from the ammunition cartridge 19 to pass through the insert passage 63 and into the bore 33, the throat insert 60 being formed of a different material than the barrel 30. As noted above, the insert passage 63 may have a relatively smooth surface (i.e. no rifling). In some alternate embodiments, however, the insert passage 63 may comprise a rifled insert passage having insert rifling 65 disposed on an inner surface thereof, wherein the insert rifling 65 may be similar to a rifling of the bore 33.
Embodiments in accordance with the present disclosure may be utilized with various types of firearms including, but not limited to, rifles, pistols, shotguns, artillery, tank barrels, or other suitable devices. Embodiments in accordance with the present disclosure may also be utilized in bolt 18 action, lever action, pump action, revolver or semi-automatic types of firearms. Embodiments in accordance with the present disclosure may also be utilized with various types of gun barrels 30 including, but not limited to, smoothbore and rifled barrels.
In use, a user selects the desired caliber of ammunition cartridge 19 they desire to fire and the desired barrel 30 to use for their firearm 10. The user installs a throat insert 60 into the throat region 70 of the bore 33 of the barrel 30, and then connects the barrel 30 in a threaded manner to the chamber body 20 as illustrated in
As ammunition cartridges are fired, the bullet (or round) traverses through the throat insert 60 and out through the bore 33 of the barrel 30. Because the throat insert 60 is positioned proximate to the chamber 24, the throat insert 60 is exposed to the most severe environment that would otherwise be experienced by the barrel 30. After repeated usage, the throat insert 60 may become worn and require replacement. The user simply removes the original throat insert 60 from the throat region 70 of the bore 30, and then installs a new throat insert 60 into the throat region 70 of the barrel 30, therefore avoiding time and expense that may otherwise be associated with repair of the barrel 30.
In addition, the chamber body 20 may become worn or damaged requiring replacement. If so, the user purchases a new chamber body 20, removes the old chamber body 20 from the receiver 14 of the rifle and the barrel 30, and then installs the new chamber body 20 between the receiver 14 and the barrel 30. When a new throat insert 60, a new chamber body 20, or both are assembled, a new pressure ring 40 may be used to provide a seal between the barrel 30 and the chamber body 20. These processes may be used to replace the throat insert 60 and/or the chamber body 20 at any time for any reason.
The present invention may be embodied in other specific forms without departing from the spirit or essential attributes thereof, and it is therefore desired that the present embodiment be considered in all respects as illustrative and not restrictive. Many modifications and other embodiments of the present disclosure will come to mind to one skilled in the art to which this invention pertains and having the benefit of the teachings presented in the foregoing description and the associated drawings. Therefore, it is to be understood that the invention is not to be limited to the specific embodiments disclosed and that modifications and other embodiments are intended to be included within the scope of the appended claims. Although methods and materials similar to or equivalent to those described herein can be used in the practice or testing of the embodiments in the present disclosure, suitable methods and materials are described above. Thus, the present disclosure is not intended to be limited to the embodiments shown, but is to be accorded the widest scope consistent with the principles and features disclosed herein.
Unless otherwise defined, all technical and scientific terms used herein have the same meaning as commonly understood by one of ordinary skill in the art to which this invention belongs. Although methods and materials similar to or equivalent to those described herein can be used in the practice or testing of the various embodiments of the present disclosure, suitable methods and materials are described above. All patent applications, patents, and printed publications cited herein are incorporated herein by reference in their entireties, except for any definitions, subject matter disclaimers or disavowals, and except to the extent that the incorporated material is inconsistent with the express disclosure herein, in which case the language in this disclosure controls. The various embodiments of the present disclosure may be embodied in other specific forms without departing from the spirit or essential attributes thereof, and it is therefore desired that the various embodiments in the present disclosure be considered in all respects as illustrative and not restrictive. Any headings utilized within the description are for convenience only and have no legal or limiting effect.
