AU2009201323B2 - Sound suppressors for firearms - Google Patents

Abstract

TITLE: SOUND SUPPRESSORS FOR FIREARMS A sound suppressor (or silencer) for firearms has a tubular body, closed by first and second end caps or walls, where the interior of the tubular 5 body is divided into a plurality of chambers by baffle members or partitions. Each baffle member or partition is formed from a bottle cap, such as a "crown seal", where, for each baffle member or partition, a central hole is formed in a top wall in alignment with holes in the first and second end caps or walls, for the passage of bullets / projectiles; and the 10 peripheral flange or rim is deformed to provide a plurality of facets or sections secured to the inner face(s) of the wall(s) of the tubular body. The facets or sections are secured so that gas passages between adjacent pairs of chambers are not aligned, forcing the propellant gasses to follow a non-liner / tortuous path to the exit of the sound suppressor. -4w 1 4'- -2LrJi rj .. to AA J

Description

P/00/011 Regulation 3.2 AUSTRALIA Patents Act 1990 ORIGINAL COMPLETE SPECIFICATION STANDARD PATENT Invention Title: "SOUND SUPPRESSORS FOR FIREARMS" The following statement is a full description of this invention, including the best method of performing it known to me/us: TITLE: SOUND SUPPRESSORS FOR FIREARMS BACKGROUND OF THE INVENTION Field of the Invention THIS INVENTION relates to sound suppressors for firearms. 5 The invention particularly relates, but is not limited, to sound suppressors (also known as "silencers") for firearms, where the term "firearms" shall include (but not be limited to): (i) small arms, such as hand guns (including revolvers and pistols); (ii) long arms or long guns (including rifles and carbines); 10 (iii) automatic weapons (including machine guns, submachine guns and automatic rifles); and (iv) air-operated firearms. The invention is particularly suitable for, but not limited to, sound suppressors for firearms of small calibre (e.g. up to 7.62mm (0.3 inches)) 15 and/or with relatively low muzzle velocities. Throughout the specification, the term "bottle cap" shall include, but not be limited to: (i) screw-caps for bottles, jars or like- containers; (ii) "crown seals", being caps having corrugated or castellated 20 peripheral flanges or rims for engagement with the mouths or necks of bottles or like-containers; and (iii) like caps or closures for bottles, jars or like-containers. Prior Art Sound suppressors, or silencers, for firearms operate by converting at 2 least a portion of the sound energy, generated when the propellant in a cartridge is ignited to propel the bullet or projectile from the firearm, into heat energy. This reduces the quantity of sound energy transmitted from the muzzle of the firearm. As a result, (i) the location of the firearm may be more 5 difficult to be established by others in the vicinity (e.g. to conceal a sniper); (ii) it reduces the likelihood of disturbing animals, birds or other live targets; and/or (iii) provides hearing protection for the firearm operator & those persons nearby, when any shot is fired. Examples of known sound suppressors, or silencers, are disclosed, in: 10 a) US 1,482,805 (Hiram Percy Maxim) b) US 2,872,848 (Karl E. Shuessler) c) US 3,748,956 (Siegfried Hubner) In the (a) Maxim and (c) Hubner disclosures, the sound suppressors, or silencers, each comprise a hollow cylindrical body, closed by front and rear 15 end walls having aligned openings therethrough to define a passage for the bullets or projectiles. The propellant gases, emerging from the muzzle of the firearm, are "slowed" within the body by a plurality of baffle members or partitions, which divide the body into a plurality of chambers. The baffle members or partitions have aligned openings therein to allow the passage of 20 the bullets or projectiles. In the (a) Maxim disclosure, the annular portions of the partitions around the openings have diametrically-opposed sections which are inclined at an angle to the longitudinal axis of the tubular body; while in the (c) Hubner disclosure, the openings in the partitions have "serrated" edges which are bent towards the rear end wall of the tubular body 3 (i.e. in the direction of travel of the bullets or projectiles). Also, in Hubner, at least one of the chambers is constructed as a "return-flow" chamber, where a tubular element, with openings in its sidewall, defines a passage through the "return-flow" chamber for the bullets / projectiles and the propellant gasses. 5 SUMMARY OF THE PRESENT INVENTION It is an object of the present inventions to provide a method for inexpensively manufacturing the baffle members, or partitions, for sound suppressors (or silencers) for firearms. It is a preferred object of the present invention to provide such a 10 method which uses inexpensive, readily available, existing materials. It is a further preferred objecting of the present invention to provide a simple and inexpensive method for manufacturing sound suppressors (or silencers) for firearms, incorporating the baffle members or partitions.. It is a further preferred object of the present invention to produce such 15 sound suppressors, which are particularly suitable for small calibre firearms and / or firearms with low muzzle velocities. It is a still further preferred object of the present invention to provide relatively simple tool(s) for the manufacture of the baffle members or partitions; and for the assembly of the sound suppressors. 20 Other preferred objects of the present invention will become apparent from the following description. In one aspect, the present invention resides in a method of manufacturing a baffle member or partition for a sound suppressor for firearms, the method including the steps of: 4 a) placing a bottle cap, having a top wall surrounded by a peripheral flange or rim, in a die; b) urging a mandrel , aligned with the die, into engagement with the bottle cap, to produce the baffle member or partition, (i) to form a hole in the 5 top wall substantially centrally thereof and (ii) to deform the peripheral flange or rim into a plurality of facets or sections operable to engage an inner face of at least one wall of a tubular body for the sound suppressor; and c) stripping or releasing the baffle member or partition from the forming die. 10 Preferably, the facets or sections are substantially equally spaced around the baffle member or partition. Preferably there are at least two facets or sections. Preferably, each of the facets or sections are profiled to conform to the inner face of the at least one wall of the tubular body, when in use. 15 Preferably, the hole is formed with a circumferential ring, deformed out of the plane of the top wall; and preferably directed to the same side of the top wall as the facets or sections. In a second aspect, the present invention resides in a baffle member or partition for a sound suppressor for firearms manufactured by the method 20 hereinbefore described. In a third aspect, the present invention resides in a manufacturing tool assembly for effecting the method of manufacturing the baffle member or partition for a sound suppressor for firearms as hereinbefore described, the assembly including: 5 a die, having a forming die and an ejector; the forming die having a forming die body, mountable on a support, with a bore therethrough, the bore having a first portion separated from a second portion, of reduced dimension(s) by an abutment face; 5 the ejector having a tubular body, dimensioned to be releasably received in the bore of the forming die body, and a head, dimensioned to be releasably received in the first portion of the bore with one face engagable with the abutment face and an (opposed) second face having forming portion engageable, in use, by the top wall of the bottle cap; and 10 a mandrel, aligned with the first portion of the bore, having at least a nose portion operable, in use, to be urged in the first portion of the bore, to co-operate with the forming die and the ejector, to form the hole in the top wall and form the facets or sections from the peripheral flange or rim. Preferably, the mandrel is connected to a hydraulic or pneumatic ram, 15 a mechanical screw, or other suitable linear (reciprocating) driving mechanism. Preferably, the ejector is a connected a second such driving mechanism, operable to cause the baffle member or partition to be stripped or released from the forming die. 20 Preferably, the tubular body of the ejector has a bore, to receive the at least nose portion of the mandrel & to allow passage of a slug, generated when the hole is formed, therethrough. In a fourth embodiment, the present invention resides in a method of manufacturing a sound suppressor for firearms incorporating a plurality of 6 baffle members or partitions, as hereinbefore described, including the steps of: a) securing a first end cap or wall to one end of a tubular body of the sound suppressor, 5 b) inserting a plurality of the baffle members or partitions into the tubular body, to divide the interior of the body into a plurality of chambers, and fixing at least some of the facets or sections to the inner face(s) of adjacent portion(s) of the at least one wall of the tubular body, to provide respective passages between adjacent chambers for the propellant gases; 10 and c) securing a second end wall or cap to the other end of the tubular body. In a fifth aspect, the present invention resides in a sound suppressor for firearms, manufactured by the method hereinbefore described, wherein: 15 the tubular body has at least one substantially cylindrical wall, or a plurality of side walls forming a substantially regular polygonal shape. Preferably, the regular polygonal shape is a square, rectangle, pentagon, hexagon, octagon or the like; and each facet or section is secured to an inner face of a respective one of the side walls. 20 Preferably, the respective passages between the adjacent chambers are each defined by the inner face(s) of the adjacent side wall(s) and by a substantially linear portion of the peripheral flange or rim interconnecting an adjacent pair of the facets or sections. Preferably, the respective passages between adjacent pairs of the 7 chambers are angularly offset, to generate non-linear paths for the propellant gasses as they travel through the sound suppressor. Preferably, adjacent baffle members are spaced by the engagement of a peripheral flange or rim of one of the baffle members or partitions 5 engaging the top wall of the other of the baffle members. In a modified embodiment, where at least one of the chambers may have a different volumetric capacity, one of the adjacent pair of the baffle members or partitions may be "reversed", so that the respective peripheral flanges or rims abut each other. 10 In a further modified embodiment, one or more spacers, e.g. collars, rings or washers, may be provided between adjacent baffle members or partitions, to produce chambers having a plurality of different volumetric capacities. Preferably, the first and second end caps or walls have holes 15 therethrough, aligned with the respective holes in the baffle members or partitions. Preferably, at least one of the first or second end caps or walls is releasably secured to the tubular body, to enable removal thereof for cleaning of the interior of the sound suppressor and/or replacement of one or 20 more of the baffle members or partitions. Preferably, at least one of the first and second end caps or walls has a screw-threaded, bayonet, or other coupling means, for releasable mounting of the sound suppressor at, or adjacent, the muzzle(s) of the firearm(s). In a sixth aspect, the present invention resides in a firearm fitted with 8 the sound suppressor as hereinbefore defined. BRIEF DESCRIPTION OF THE DRAWINGS To enable the invention to be fully understood, preferred 5 embodiments will now be described with reference to the accompanying drawings, in which: FIG. 1 is a schematic side view of the tool components used to manufacture the baffle members or partitions from bottle caps / crown seals; FIG. 2 is a schematic sectional side of the tool components as 10 assembled prior to the manufacture of a baffle member or partition from the crown seal included in the drawing; FIG. 3 is an end view of the mandrel, taken in the direction of arrow 3 in FIG. 2; FIG. 4 is a bottom, or "open side", view of the baffle member or 15 partition; FIG. 5 is a top, or "closed side", view of the baffle member or partition; FIG. 6 is a sectional side view of the baffle member or partition taken on line A-A on FIG. 4; FIG. 7 is a similar view taken on line B-B on FIG. 4; 20 FIG. 8 is an "exploded" schematic side view of the tubular body for the sound suppressor; and FIG. 9 Is a schematic sectional side view of the assembled sound suppressor.

9 DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS In the embodiment illustrated in FIGS. 1-9, a sound suppressor 10 for a small calibre/low velocity firearm, e.g. a .22 calibre rifle or .25 calibre pistol (not shown), is assembled incorporating a plurality of baffle members 20, 5 each manufactured from a crown seal of the type used to close bottles, e.g. which may contain alcoholic beverages such as beer; still, aerated or carbonated non-alcoholic beverages, such as water, cordials, soft drinks; or foodstuffs, such as cooking oils or sauces; contained in glass bottles. NB. It would be readily apparent to the skilled addressee that the 10 present invention is also applicable to screw-type caps or closures, with suitable modification to the tool components to be hereinafter described. Typically, a crown seal CS has a (slightly convex) top wall 21, surrounded by a (slightly divergent) peripheral flange 22, with a "corrugated" or "castellated" profile in end view. 15 To form the baffle members 20 from the crown seal CS, the crown seal CS is placed in a die D, comprising a forming die 30 and ejector 40; and the crown seal CS is deformed when a mandrel 50 is forced into an engagement therewith to both punch a hole 23 centrally in the top wall 21, and to deform the peripheral flange 22 into, in this embodiment, three facets 20 24, each pair of facets 24 being interconnected by a respective substantially linear portion 25 of the peripheral flange 22. (The final shape of the baffle member 20 will be hereinafter described with reference to FIGS. 4-7). The die D has a forming die 30, with a tubular forming die body 31 having a screw- threaded shank 32, surmounted by an enlarged annular 10 head 33. The screw threaded shank 32 may be securely mounted to a support S, e.g. a work bench, press, or the like. A profiled first portion 34 of a bore through the forming die body 31 is of larger diameter than the second portion 35 thereof, and is connected 5 thereto by an annular abutment face 36. The other end of the first portion 34 of the bore is convergently profiled to initially centre the crown seal CS relative to the die D, and to then assist , the deformation of the peripheral flange 22 of the crown seal CS by the mandrel 50. An ejector 40 has a tubular ejector body 41 slidably receivable within 10 the second portion 35 of the bore of the forming die 30; and an annular head 42, receivable in the first portion 34of the bore of the forming die 30, and adapted to be supported by the abutment face 36. A plain bore 43, through the ejector body 41, enables the "slug", punched from the top wall 21of the crown seal CS, when the hole 23 therein is formed, to be releasably ejected. 15 The head 42 of the ejector 40 has a concave recess or depression 44, profiled substantially complimentary of the top wall 21 of the crown seal CS, to support the top wall 21 as the hole 23 is punched therein and as the peripheral flange 22 is deformed. The ejector 40 is connected to a reciprocating linear driver, e.g. a 20 hydraulic or pneumatic ram R, (shown in dashed lines), which is operable to move the ejector 40, in the direction of arrow ED, relative to the forming die 30, to thereby enable to the baffle member 20 to be ejected from the die D. The mandrel 50 has a cylindrical mandrel body 51, connected to the ram MR of a hydraulic or pneumatic cylinder C (both shown in dashed lines).

11 The ram MR is operable to move the mandrel 50 in the direction of arrow MD, to enable the mandrel 50 to deform the crown seal CS to form the baffle member 20. The mandrel 50 is coaxially aligned with the first portion 34of the bore 5 in the forming die 30, and is dimensioned to be received therein. The mandrel 50 has a nose portion 53, profiled as illustrated in FIG. 3, with a central closed bore 54 and three protrusions 55, adapted to inwardly deform the peripheral flange 22 of the crown seal CS into three, equally spaced, linear portions 25, each interconnected by respective curved facets 10 24. (The facets 24 will be secured to the inner face of the wall 12 of the tubular body 11 of the sound suppressor 10, as to be hereinafter described). As illustrated in FIGS. 4-7, each baffle member 20 has a top wall 21 with a central hole 23 therethrough; and where the peripheral flange 22 has been deformed, from the original substantially-circular shape, into three 15 equally spaced, convexly curved, facets 24, where each pair of facets 24 is interconnected by a substantially linear portion 25 of the peripheral flange 22. The linear portions 25 of the peripheral flange 22 are configured to co operate with the wall 12 of the suppressor body 11, to form gas passages G for the propellant gases; and to also act as "spacers" between the top walls 20 21 of the adjacent baffle members 20, to form the respective chambers C in the sound suppressor 10, to be hereinafter described. The hole 23 is surrounded by a circumferential ring 26, deformed out of the plane of the top wall, and directed to the same side thereof as the peripheral flange 22.

12 The sound suppressor 10 has a cylindrical suppressor body 11, which is closed, on assembly, by first and second end caps 13, 14, to be hereinafter described. The first end cap 13 has a tubular cap body 15, with an annular flange 5 16, where the first cap body 15 is dimensioned to be received in one end of the suppressor body 11, and is secured thereto e.g. by welding the annular flange 16 to the suppressor body 11. The first end cap 13 has a screw-threaded bore 17, arranged to be coupled to complimentary screw threads on the muzzle of the firearm, or on 10 a coupling member fitted mounted on the muzzle of the firearm, to enable the sound suppressor to be detachably mounted on the firearm. An expansion chamber spacer tube 18 is placed in the suppressor body 11, and engages the inner annular face of the first end cap body 15, to space the first adjacent baffle member 20 therefrom to form the expansion 15 chamber EC for the propellant gases. As illustrated in FIG. 9, a plurality of the baffle members 20 are placed within the suppressor body 11, where the peripheral flange 22 of the first baffle member 20 engages the adjacent annular end face of the expansion chamber spacer tube 18; and the peripheral flanges 22of subsequent baffle 20 members20 engage the respective top walls 21 of the preceding baffle members 20. The suppressor body 11 is closed by the second end cap 14, which is provided in the form of a washer which is welded to the other end of the suppressor body, and the hole 19 therethrough is aligned with the screw- 13 threaded bore 17 of the first end cap 13 and with the holes 23 in the top walls 21 of the baffle members 20. Each pair of baffle members 20 form a respective chamber c within the suppressor body 11, through which the propellant gases pass, to cause 5 at least a portion of their sound energy to be converted to heat energy, which is absorbed by the suppressor body 11 and the baffle members 20; and the facets 24 of one pair of the baffle members 20 is angularly offset to the facets 24 of the other of the pair of baffle members 20, so that the gas passages G, defined by the linear portions 25 of the peripheral flanges 22 of 10 the baffle members 20, and the wall 12 of the suppressor body 11,define a non-linear, or torturous path for the propellant gases. This reduces their velocity, and so increases the residence time within the sound suppressor 0, to increase the conversion of the sound energy to heat energy, with consequent increased sound reduction. 15 It would be readily apparent to the skilled addressed that the crown seals CS are readily available and inexpensive, and so provide a advantageous source for the baffle members 20. It would also be readily apparent to the skilled addressed that, one, or both, of the first or second end caps 13,14 may be screw-threadably, or 20 otherwise coupled, to the suppressor body 11 to enable the end cap(s) 13, 14 to be removed for cleaning of the interior of the suppressor body 1 and/or replacement of the baffle members 20. It will be noted by the skilled addressee that the circumferential ring 26 around the holes 23 in the baffle members 20 are preferably directed 14 "counter-current" to the primary flow of the propellant gases, and so will tend to urge the gases outwardly, but partially against the gas flow, towards the gas passages G, to further increase the residence time. In the embodiment illustrated, the suppressor body 11 is substantially 5 cylindrical in end view. However, the skilled addressee will appreciate that the suppressor body 11 may be of e.g. regular polygonal shape ( including square, pentagon, hexagon, octagon); or other suitable shape. Furthermore, the skilled addressee will appreciate that for, e.g. a square or octagonal shape, the baffle members 20 may have four facets 24 10 to be secured to the inner faces of respective side walls 11 forming the suppressor body 11. (For an octagonal shape, a number of the baffle members 20 could have four facets 24, and the other (e.g. alternating) baffle members 20 could have eight facets 24). To produce chambers C of different volumetric capacities within the 15 sound suppressor 10, one of the baffle members 20, in one or more of the pairs of baffle members 20, may be "reversed", so that the peripheral flanges 22 are in "butting" engagement, resulting in a chamber C' of approximately double the volumetric capacity compared to the volumetric capacity of the chambers C illustrated in FIG. 9. 20 Alternatively, chambers C of different volumetric capacities could be produced by placing "spacer rings" (not shown) between the top wall 21 of one baffle member 20 in a pair and the peripheral flange 22 of the second baffle member 20 of the pair. It will be readily apparent to the skilled addressee that while the 15 invention is particularly suitable for the manufacture of sound suppressors for firearms of small calibre and/or small muscle velocity, the invention can be readily adaptable to firearms of larger calibres and/or higher muzzle velocities, by a selection / deformation of different caps or closures, e.g. the 5 caps or closures for larger-mouth jars. The skilled addressee will readily appreciate that the present invention provides a simple, inexpensive, method of manufacturing the baffle members for sound suppressors from existing materials; and a method of manufacturing the sound suppressors per se. 10 Various changes and modifications may be made to the embodiments, described and illustrated, without departing from the present invention.

Claims (22)

1. A method of manufacturing a baffle member or partition for a sound suppressor for firearms, the method including the steps of: a) placing a bottle cap, having a top wall surrounded by a peripheral 5 flange or rim, in a die; b) urging a mandrel , aligned with the die, into engagement with the bottle cap, to produce the baffle member or partition, (i) to form a hole in the top wall substantially centrally thereof and (ii) to deform the peripheral flange or rim into a plurality of facets or sections operable to engage an inner face 10 of at least one wall of a tubular body for the sound suppressor; and c) stripping or releasing the baffle member or partition from the forming die.

2. A method as claimed in Claim 1, wherein: the facets or sections are substantially equally spaced around the 15 baffle member or partition.

3. A method as claimed in Claim or Claim 2, wherein: there are at least two facets or sections.

4. A method as claimed in any one of Claims 1 to 3, wherein: each of the facets or sections are profiled to conform to the inner 20 face of the at least one wall of the tubular body, when in use.

5. A method as claimed in any one of Claims 1 to 4, wherein: the hole is formed with a circumferential ring, deformed out of the plane of the top wall; and directed to the same side of the top wall as the facets or sections. 17

6. A baffle member or partition for a sound suppressor for firearms manufactured by the method as claimed in any one of Claims 1 to 5.

7. A manufacturing tool assembly for effecting the method of manufacturing the baffle member or partition for a sound suppressor for 5 firearms, as claimed in any one of Claims 1 to 5, the assembly including: a die, having a forming die and an ejector; the forming die having a forming die body, mountable on a support, with a bore therethrough, the bore having a first portion separated from a second portion, of reduced dimension(s) by an abutment face; 10 the ejector having a tubular body, dimensioned to be releasably received in the bore of the forming die body, and a head, dimensioned to be releasably received in the first portion of the bore with one face engagable with the abutment face and an (opposed) second face having forming portion engageable, in use, by the top wall of the bottle cap; and 15 a mandrel, aligned with the first portion of the bore, having at least a nose portion operable, in use, to be urged in the first portion of the bore, to co-operate with the forming die and the ejector, to form the hole in the top wall and form the facets or sections from the peripheral flange or rim.

8. An assembly as claimed in Claim 7, wherein: 20 the mandrel is connected to a hydraulic or pneumatic ram, a mechanical screw, or other suitable linear (reciprocating) driving mechanism.

9. An assembly as claimed in Claim 7 or Claim 8, wherein: the ejector is a connected a second such driving mechanism, operable to cause the baffle member or partition to be stripped or released 18 from the forming die.

10. An assembly as claimed in any one of Claims 7 to 9, wherein: the tubular body of the ejector has a bore, to receive the at least nose portion of the mandrel & to allow passage of a slug, generated when the hole 5 is formed, therethrough.

11. A method of manufacturing a sound suppressor for firearms incorporating a plurality of baffle members or partitions, as claimed in Claim 6, including the steps of: a) securing a first end cap or wall to one end of a tubular body of the 10 sound suppressor, b) inserting a plurality of the baffle members or partitions into the tubular body, to divide the interior of the body into a plurality of chambers, and fixing at least some of the facets or sections to the inner face(s) of adjacent portion(s) of the at least one wall of the tubular body, to provide 15 respective passages between adjacent chambers for the propellant gases; and c) securing a second end wall or cap to the other end of the tubular body.

12. A sound suppressor for firearms, manufactured by the method as 20 claimed in Claim 11, wherein: the tubular body has at least one substantially cylindrical wall, or a plurality of side walls forming a substantially regular polygonal shape.

13. The sound suppressor as claimed in Claim 12, wherein: the regular polygonal shape is a square, rectangle, pentagon, 19 hexagon, octagon or the like; and each facet or section is secured to an inner face of a respective one of the side walls.

14. The sound suppressor as claimed in Claim 12 or Claim 13, wherein: the respective passages between the adjacent chambers are each 5 defined by the inner face(s) of the adjacent side wall(s) and by a substantially linear portion of the peripheral flange or rim interconnecting an adjacent pair of the facets or sections.

15. The sound suppressor as claimed in Claim 14, wherein: the respective passages between adjacent pairs of the chambers are 10 angularly offset, to generate non-linear paths for the propellant gasses as they travel through the sound suppressor.

16. The sound suppressor as claimed in any one of Claims 12 to 15, wherein: adjacent baffle members are spaced by the engagement of a 15 peripheral flange or rim of one of the baffle members or partitions engaging the top wall of the other of the baffle members.

17 The sound suppressor as claimed in Claim 16, wherein: where at least one of the chambers has a different volumetric capacity, one of the adjacent pair of the baffle members or partitions is 20 "reversed", so that the respective peripheral flanges or rims abut each other.

18. The sound suppressor as claimed in Claim 16, wherein: one or more spacers, such as collars, rings or washers, are provided between adjacent baffle members or partitions, to produce chambers having a plurality of different volumetric capacities. 20

19. The sound suppressor as claimed in any one of Claims 12 to 18, wherein: the first and second end caps or walls have holes therethrough, aligned with the respective holes in the baffle members or partitions. 5

20. The sound suppressor as claimed in any one of Claims 12 to 19, wherein: at least one of the first or second end caps or walls is releasably secured to the tubular body, to enable removal thereof for cleaning of the interior of the sound suppressor and/or replacement of one or more of the 10 baffle members or partitions.

21. The sound suppressor as claimed in any one of Claims 12 to 20, wherein: at least one of the first and second end caps or walls has a screw threaded, bayonet, or other coupling means, for releasable mounting of the 15 sound suppressor at, or adjacent, the muzzle(s) of the firearm(s).

22. A firearm fitted with the sound suppressor as claimed in any one of Claims 12 to 21. 20 21 THIS PAGE INTENTIONALLY LEFT BLANK