WO2007064442A2

WO2007064442A2 - Mortar with integral mortar carrier

Info

Publication number: WO2007064442A2
Application number: PCT/US2006/042970
Authority: WO
Inventors: Timothy J. Doering; Dennis W. Borgwarth; Bradley J. Breeggeman; Ryan C. Lakeman
Original assignee: Bae Systems Land & Armaments L.P.
Priority date: 2005-11-29
Filing date: 2006-11-02
Publication date: 2007-06-07
Also published as: WO2007064442A3

Abstract

A mortar, having a mortar tube assembly, a base plate assembly operably couplable to the mortar tube assembly, and a mortar mount bipod assembly operably couplable to the mortar tube assembly includes a mortar carrier assembly, the mortar carrier assembly being operably coupled to a mortar assembly, the mortar assembly comprising the mortar tube assembly, the base plate assembly, and the mortar mount bipod assembly in a unitized cooperative assembly for the ready transportation thereof. A mortar carrier assembly is further included and additionally a method of assembling a mortar into a readily transportable state is included.

Description

MORTAR WITH INTEGRAL MORTAR CARRIER

Field of the Invention

This invention refers to a mortar carrier which includes a transportation holder for a mortar assembly and more specifically to a tubular framework for unitizing the mortar assembly while attached to the mortar for easier transportation and quicker deployment thereof.

Background of the Invention

A mortar assembly is typically comprised of a tube assembly, a base plate assembly, and a bipod mount assembly. The tube assembly consists of a barrel or tube that is sealed at the breech end with a removable breech plug which houses a removable firing pin. A cone shaped blast attenuator device is typically fitted at the muzzle end of the tube to reduce firing noise and flash. The base plate assembly includes a base plate that is a one piece construction that supports the breech end of the tube and assists in aligning the mortar during firing. A foot on the breech plug of the tube is removably locked into a rotatable socket in the base plate. The bipod mount assembly comprises a bipod having elevating and traversing mechanisms. The bipod provides front support for the barrel and carries the gears necessary to lay, or aim, the mortar. The bipod includes a traversing screw assembly which is pivoted on an arm attached to the elevating leg. An elevating shaft is contained in the elevating leg and adjusted by an elevated hand crank. A plane leg is fitted to a stud on the elevating leg and is secured by a leg locking hand crank. Both legs are typically fitted with a disk shaped foot with a depending spike that digs into the ground to prevent the mount from slipping when firing. The bipod mount assembly cooperates with the tube in supporting the tube at a desired angle for firing rounds from the mortar. The tube in effect constitutes the third support leg.

Modern warfare has placed increased emphasis on the need for mobility, rapid deployment of troops and their armaments, and reduced logistical support of the troops on the line. A lightweight, readily-portable mortar system has been a long sought after goal to assist infantry personnel in moving rapidly into offensive firing positions with minimum assistance from supportive groups. Mortars provide unique indirect (plunging) fire that is responsive to the ground maneuver commander on the scene. Their rapid, high angle, plunging fires are invaluable against dug in enemy troops and targets in defilade, which are minimally vulnerable to attack by direct fire. Mortars allow maneuver commanders to quickly place indirect, relatively heavy fire on the enemy, independent of whether the maneuver commander has been allocated supporting artillery. Mortars are about the heaviest weapon in terms of fire delivered that is directly transportable by a relatively small unit of infantry. Typically, light forces use wheeled vehicles or alternatively hand carry mortars into firing positions. Some light mortars are man packed across all terrain. Mortars are found in sizes ranging from 60 mm up to 120 mm. The lightest weight mortars weigh about 18 pounds while the heaviest weigh more than 500 pounds. The mortar is very difficult to transport in an assembled position and is typically broken down prior to transport. The entire system, comprising the assembled tube assembly, base plate assembly, and bipod mount assembly, is both heavy and awkward.

The typical solution has been to dismantle the mortar for transportation into the three assemblies noted above and transport each assembly independently. While this divides the mortar weight into smaller packages it puts the operational unit at disadvantage for it must first assemble the mortar before firing. This becomes a time-consuming task, particularly if all of the elements assigned to carry the pieces fail to arrive simultaneously at the firing location. Furthermore, the mortar pointing mechanism has several degrees of freedom which can require several crewmen to set up. Mortar tubes are frequently very often hot after burst fire and sustained fire operations. Disassembly of a hot mortar after firing can be dangerous for the crew. Components of a disassembled mortar can also sustain damage as separate components during transport due to jostling and handling errors.

Other solutions to enhance the transportability of mortars have involved attempts to decrease the weight of certain mortar elements. Prior art methods for achieving weight reduction mainly focus on simple material substitution, without significant structural changes in design in order to effect a meaningful weight reduction.

Thus there is a need for a system to assist the operational unit in transporting a mortar without sacrificing time to first fire.

Summary of the Invention The mortar carrier of the present invention substantially meets the aforementioned needs.

The mortar carrier of the present invention is a device used to unitize and hold a ground fired mortar together as a single unit allowing it to be moved without disassembly, allowing ease of transport, either manually by troops or in a vehicle, and also protects the crew from contact with a hot tube after firing. The mortar carrier structure also provides mounting space for the mortar optical sight box and common tools used by the mortar crew such as aiming stakes.

As noted above, ground fired mortars typically consist of three major components: the tube, the base plate and the bipod. The components are conventionally transported separately in a vehicle or manually carried by dismounted troops. The objective of the mortar carrier of the present invention is to unitize the three mortar components together, thereby allowing ease of transport either by troops or in a vehicle. The mortar carrier is easily coupled to the mortar base plate and is easily secured to the mortar tube with a single pin. The mortar carrier is constructed primarily of a welded tubular structure, using lightweight mounting yokes to interface with the mortar tube. The structure also provides mounting space for the mortar optical sight box and common tools used by the mortar crew.

The advantages of the present invention include: (a) the unitized mortar and mortar carrier can be moved in one assembly by one or two crewmen instead of breaking the mortar assembly down into its three major component assemblies; (b) the unitized mortar is more easily moved into and out of vehicles and across terrain, thereby minimizing the possibility of component assembly damage; (c) the mortar tube does not have to be handled to attach to or detach from the mortar carrier, thereby protecting the crew from burns from a hot fired tube; (d) the unitized mortar is more easily stored in an upright orientation that precludes damage; (e) the unitized mortar is more easily transported and lifted over mountainous and rugged terrain; and (f) the mortar carrier has a "sled" configuration, allowing the crew to manually pull the mortar along the ground in a unitized assembly.

The mortar carrier of the present invention is a welded tubular structure with interface points to hook into available physical features on the mortar base plate and on the tube. Additional components, constructed of lightweight polymer material are fastened to the structure to provide two interface yokes to the mortar tube. Once the tube is positioned in the yokes and the structure hooked onto the base plate, a respective coupler is used to couple the yokes to the mortar tube, thereby capturing the mortar assembly in a single readily transportable unit with the mortar carrier.

Other features that may be added to enhance the utility of the mortar carrier include wheels, attachments for ammunition storage, attachments for additional system tools and fire control components and provisions for the attachment of pulling devices such as rope or chain. Attachment for floatation devices to enable water fording may also be added.

An embodiment of the present invention includes a unitized mortar having a unique mortar carrier assembly having a tubular metal strut assembly that cradles the mortar tube while restraining the mortar base plate and the mortar bipod supports. The tubular metal strut assembly includes a muzzle fastener system and a base fastener system. The muzzle fastener system includes a muzzle yoke that cradles the mortar tube and muzzle lock for maintaining the mortar muzzle in the cradled position. The base fastener system includes a base yoke that cradles the base of the mortar tube as well as acts as a pivot point when attaching the present invention to the mortar. The base fastener system further includes base strut hooks which slidingly engage the base plate of the mortar. The base strut hooks prevent the mortar from moving within the plane of the strut assembly, specifically the mortar cannot slide out of the cradle when lifted vertically. The present invention is a mortar, having a mortar tube assembly, a base plate assembly operably couplable to the mortar tube assembly, and a mortar mount bipod assembly operably couplable to the mortar tube assembly. The mortar includes a mortar carrier assembly, the mortar carrier assembly being operably coupled to a mortar assembly, the mortar assembly comprising the mortar tube assembly, the base plate assembly, and the mortar mount bipod assembly in a unitized cooperative assembly for the ready transportation thereof. The present invention is further a mortar carrier assembly and is additionally a method of assembling a mortar into a readily transportable state.

Brief Description of the Drawings Fig. 1 is a front perspective view of the mortar of the present invention;

Fig. 2 is a rear perspective view of the mortar of the present invention; Fig. 3 is a side perspective view of the mortar of the present invention; Fig. 4 is an alternate side perspective view of the mortar of the present invention; Fig. 5 is a perspective view of the mortar tube partially detached from the strut of the present invention;

Fig. 6 is an underside perspective view of the mortar tube partially detached from the strut of the present invention;

Fig. 7 is a perspective view of the present invention with mortar tube detached from the strut; Fig. 8 is an alternate perspective view of the present invention without sight box;

Fig. 9 is a perspective view of the present invention as depicted in Fig. 8; Fig. 10 is a perspective view of the present invention including a phantom depiction of wheels coupled to the rails; and Fig. 11 is a perspective view of the present invention including a phantom depiction of inflatable flotation bladders coupled to the rails.

Detailed Description of the Drawings The mortar 18 of the present invention is illustrated in Figs. 1-4 with the mortar carrier 10 attached. Mortar 18 is an assembly comprised of a mortar tube assembly 20, a mortar mount or bipod assembly 19 and a base plate assembly 21. hi a first embodiment, the mortar assembly 18 is an 81 mm mortar, such as deployed by the U.S. Army under the designation M252. Total weight for mortar assembly 18, exclusively of mortar carrier 10, is approximately ninety pounds. The mortar tube assembly 20 of the mortar assembly 18 includes a mortar tube 20a having a first, breech end or tube base 22 and a second end or tube muzzle 23. At the tube muzzle 23, a cone shaped blast attenuator device 36 is preferably fitted about the circumference of tube muzzle 23 to reduce noise when firing. The firing mechanism for mortar assembly 18 is disposed at the tube base 22. A removable breech plug 22a seals the tube base 22 of the tube 20a and houses a removable firing pin (not shown). At the tube base 22, a foot 22b is seatable into a receptacle defined in the mortar base plate assembly 21, thereby coupling the mortar tube 20 to the base plate assembly 21. This mating of the tube 20a and the base plate assembly 21 is described in greater detail below.

The base plate assembly 21 is typically formed of a one piece construction that acts to support the mortar tube 20a and to assist in aligning the mortar assembly 18 for firing. The base plate assembly 21 of an embodiment is the U.S. Army M3A1 base plate. During firing, the foot 22b of the tube base 22 on the mortar tube 20a is locked to a rotatable socket 21a on the base plate 21.

The base plate 21 is best depicted in Fig. 4 and has a bowl-like configuration wherein a base plate collar 33 defines a ring about a base plate bowl 30. Base plate spades 31 depend from the base plate collar 33 and are designed for digging into the ground to stabilize the mortar assembly 18. The base plate spades 31 are generally triangular in shape with a pointed aspect disposed to first contact and cut into the ground surface. The base plate bowl 30 is coupled to the base plate collar 33 by a plurality of base plate spokes 34 which extend radially inward from base plate collar 33 to intersect at center plate disk 60. The base plate spokes 34 are disposed equiangularly about the circumference of base plate collar 33. Base plate ribs 32 form a framework to support base plate spokes 34. Base plate ribs 32 define depending strengthening gussets for the base plate ribs 32 and extend radially outward from center plate disk 60 to the base plate spades 31. The mortar mount bipod assembly 19 of the mortar assembly 18 is coupled to the mortar tube 20a proximate the tube muzzle 23 by means of a bipod barrel clamp 61. hi a first embodiment, the mortar bipod is the Ml 77 Mount as deployed by the United States Army. The mortar mount bipod assembly 19 provides upper front support for mortar tube 20a and carries the traversing mechanism 24 necessary to lay (aim) the mortar 18. The mortar mount bipod assembly 19 includes generally the traversing mechanism 24 disposed proximate the tube muzzle 23 mortar tube 20a.

The elevation guide leg 27 is operably coupled to the transversing mechanism 24. The elevation guide leg 27 includes a guide leg foot 35 at a distal end thereof for contact with the ground. Fixed leg pivot 28 is located at an intermediate point on elevation guide leg 27. The fixed leg 25 is coupled to fixed leg pivot 28 to form the second leg of the mount bipod assembly 19. The fixed leg pivot 28 also includes a fixed leg lock 29 for keeping fixed leg 25 in a desired position, either retracted transport disposition or in an extended angled disposition. When not in the extended, ground engaging position, fixed leg lock 29 may loosened so that fixed leg 25 is folded along side elevation guide leg 27 in the retracted, transport disposition.

The mortar carrier 10 of the present invention provides means to keep the mortar assembly 18 unitized with the tube 20a connected to the base plate assembly 21, the bipod assembly 19 being coupled to the tube 20a. This unitized disposition is useful during transportation of the mortar assembly 18 by forming a lightweight framework about the mortar assembly 18 that both restrains the three individual mortar elements described above and allows for easier handling. The mortar carrier 10 includes mortar carrier assembly 11, muzzle yoke 12 and base yoke 16. The mortar carrier assembly 11 generally comprises a framework of tubular construction forming a valley or cradle for placement of mortar tube 20a and a coupler for base plate assembly 21. The mortar carrier assembly 11 further forms a sled to assist in transporting and carrying the mortar assembly 18.

As illustrated most particularly in Figs. 5-9, the mortar carrier 10 includes a barrel yoke strut 39, supporting the muzzle yoke 12, and a base yoke strut 40, supporting the base yoke 16. The barrel yoke strut 39 and the base yoke strut 40 are separated by side rail struts 41a, 41b. The barrel yoke strut 39 is disposed to provide a mounting location for muzzle yoke 12. Likewise, the base yoke strut 40 is disposed to provide a mounting location for base yoke 16. Side rail struts 41a and 41b run generally parallel to each other until reaching intermediate point 50 at which point the rail struts 41a and 41b turn inward at a converging angle so as to mate with the respective ends of the barrel yoke strut 39. Runner struts 38a and 38b intersect the ends of side rail struts 41a and 41b at respective points 64 and 65. The runner struts 38a and 38b are disposed generally parallel to each other until reaching intermediate converging point 51 wherein they converge towards the junction of barrel yoke strut 39 with side rail struts 41a and 41b. In an embodiment, a sight box 14 is mounted to the mortar carrier assembly 11. To effect such mounting, a sight box cradle 42 is disposed between side rail struts 41 and 41b. V-shaped cradle supports 43a-d connect at a first end to side rail struts 41a and 41b, respectively, and at the second end to runner strut 38a and 38b respectively. Cradle supports 43 a-d run perpendicular to side rail struts 41a and 41b. Sight box cradle supports 42a, 42b are disposed between the cradle supports 43 a-d so that each end of the respective sight box cradle supports 42a, 42b is connected to a respective two of the cradle supports 43 a-d. For example, sight box cradle 42a is connected at a first end to cradle support 43a and at a second end to cradle support 43b. Sight box backing plates 44a and 44b extend perpendicular to sight box cradle supports 42a, 42b. Sight box backing plates 44a, 44b are in a first embodiment simply metal plates, although they too could be constructed of tubular steel. The sight box 14 is mounted flush on the outward directed face of the sight box backing plates 44a, 44b.

An accessory carrier 15, which provides a location to hold sighting stakes or other equipment, is further optionally included. The accessory carrier 15 is a pouch that has an inner volume defined therein for retaining the sighting stakes, towing straps or other equipment. The accessory carrier 15 is mounted exterior to the cradle defined by the mortar carrier assembly 11 and is fastened to the struts 38b and 41b, as depicted in Figs. 5-7

A base cross support 45 is disposed proximate the base plate assembly 21 of the mortar assembly 18. The base cross support 45 is disposed perpendicular to the rail struts 41a and 41b. Strut hook supports 46a and 46b extend from base cross support 45 to base yoke strut 40. Base strut hooks 17 (see Figs. 4 and7) are mounted to strut hook support 46a, 46b. The base strut hooks 17 are utilized to fixedly couple the base plate assembly 21 to mortar tube assembly 20 during transportation, effectively unitizing the mortar assembly 18. Runner struts 38a and 38b form a rounded corner 53 proximate the mortar base plate 21 to assist in rotating the mortar carrier 10 (and the attached mortar assembly 18) between a horizontal and a vertical disposition. Muzzle yoke 12, as best illustrated in Figs. 5 and 7-9, includes muzzle collar 62 and muzzle lock 13. Muzzle collar 62 is a U-shaped yoke disposed on barrel yoke strut 39. Muzzle yoke 62 has a mounting saddle 54 which is sized to mate with barrel yoke strut 39. Fasteners 55 are inserted through bores defined perpendicular to muzzle collar 62 through bores in registry with bores (not shown) defined in the barrel yoke strut 39 to couple the muzzle yoke 12 to the mortar carrier assembly 11. The muzzle collar 62 also includes muzzle saddle 56 for partially enclosing and capturing the mortar tube 20a. At the distal ends of muzzle saddle 56, muzzle lock 13 is disposable across the opening of the muzzle saddle 56 to secure mortar tube 20a in engagement with the mortar carrier 10. The muzzle lock 13 can be a metal rod pivotable or extendable from one end with locking or fastening means at the opposing end. It is also envisioned that muzzle lock 13 could incorporate a strap secured at a first end and fastenable at a second end.

At the opposing end of mortar tube 20a, mortar carrier 10 is attached to mortar assembly 18 by operation of the base fastener 16. See Figs. 8 and 9. The base fastener 16 includes tube saddle 57, mounting saddle 58 and hook fasteners 49. Tube saddle 57 is sized to mate with the tube base 22 of mortar 18. Tube saddle 57 has a U-shaped yoke connected to the strut assembly 11 for coupling the mortar tube 20a relative to mortar carrier assembly 11. The mounting saddle 58 is disposed to mount with base yoke strut 40 by way of fasteners 64. Fasteners 64 are inserted through bores defined perpendicular to mounting saddle 58 and through bores in registry with such bores (not shown) defined in the base yoke strut 40 to couple the muzzle yoke 12 to the mortar carrier assembly 11. As illustrated in Fig. 7, base strut hooks 17 are comprised of hook spacer 47 and hook flange 48. Hook spacer 47 is sized according to the thickness of mortar base plate collar 33. Hook flange 48 extends beyond the length of hook spacer 47 so as to secure mortar carrier 10 to base plate 21. Hook flanges 48 are directed distally from mortar 18. Hook fasteners 49 are inserted perpendicularly through hook spacer 47 and hook flange 48 to mount base strut hooks 17 to strut hook support 46a and 46b, respectively. As illustrated by Fig. 4, base lock hooks 17 extend from strut assembly 11 to engage base plate collar 33. hi operation, as depicted in Figs. 5-7, connect to the mortar carrier assembly 10 of the present invention to a mortar assembly 18, the mortar assembly 18 is maintained in an assembled disposition wherein the mortar mount bipod assembly 19 and base plate assembly 21 are attached to the mortar tube assembly 20. The mortar carrier assembly 10 is placed on the opposing side of mortar mount bipod assembly 19 so that bipod guide leg 27 and fixed leg 25 extend away from mortar carrier assembly 10. The mortar carrier assembly 10 is lowered onto base plate assembly 21 so that tube saddle 57 mates with the tube base 22. The mortar carrier assembly 10 is then backed away from the tube base 22 so that base strut hooks 17 can slidingly engage base plate collar 33 through base plate well openings 37. Tube saddle 57 acts as a pivot point during the attachment of mortar 18 to strut assembly 11. Mortar carrier 10 thus pivots about base fastener 16 so that muzzle fastener 12 can engage tube muzzle 23. Tube muzzle 23 is inserted into muzzle collar 12 and held in place by action of muzzle lock 13. The mortar carrier assembly 10 of the present invention can then be rotated about base corner 53 of strut assembly 11 so that the mortar bipod assembly 19 can be placed in a retracted disposition. The mortar assembly 18 is now ready for transportation. Additional tie downs may be applied to maintain the mortar bipod assembly 19 in a retracted position. Furthermore, once the mortar assembly 18 is disposed within the mortar carrier assembly 10, a variety of harness arrangements are envisioned for dragging, carrying or loading the mortar assembly 18.

The depiction of Fig. 10 includes a phantom depiction of wheels 70 coupled to the rails 38a, 38b respectively. The wheels 70 are depicted in pairs on an axle 72, although a single wheel 70 could as well be employed at each axle 72. The axle passes through and is supported by a bore 74 defined transverse to the respective rail 38a, 38b.

The depiction of Fig. 11 includes a phantom depiction of inflatable flotation bladders 80 coupled to the rails 41a, 41b. The bladders 80 are preferably of the type that is inflatable by means of a compressed air bottle. As the total weight of mortar assemblylδ unitized with the mortar carrier assembly 10 is no more than 120 lbs. for an 81mm mortar, the bladders 80 need have no more flotation capability than a bladder typically employed for the flotation of an adult person. Although two bladders 80 are depicted, a single bladder 80 spanning the rails 41a, 41b or more than two bladders 80 could also be employed. Preferably, the bladders 80 are coupled to the respective rails 41a, 41b just prior to making a ford by a readily disengagable means, such as hook and pile straps. The inflated bladders 80 may then be readily discarded after the ford is complete.

While the mortar carrier assembly for a mortar assembly has been shown and described in detail, it is obvious that this invention is not to be considered as limited to the exact form disclosed, and changes in detail and construction may be made therein within the scope of the invention without departing from the spirit thereof.

Claims

1. A mortar, having a mortar tube assembly, a base plate assembly operably couplable to the mortar tube assembly, and a mortar mount bipod assembly operably couplable to the mortar tube assembly, the mortar comprising: a mortar carrier assembly, the mortar carrier assembly being operably coupled to a mortar assembly, the mortar assembly comprising the mortar tube assembly, the base plate assembly, and the mortar mount bipod assembly in a unitized cooperative assembly for the ready transportation thereof.

2. The mortar of claim 1, the mortar carrier assembly defining a cradle for supporting the mortar assembly.

3. The mortar of claim 1, the mortar carrier assembly effecting a removable, fixed coupling of the mortar tube assembly and the base plate assembly.

4. The mortar of claim 1, the mortar carrier assembly having a sled configuration for transporting the mortar assembly in cooperation with the mortar carrier assembly along the ground in a unitized assembly.

5. The mortar of claim 1, the mortar carrier assembly having first and second couplings for coupling the mortar carrier assembly to the mortar tube assembly and a third coupling for coupling the mortar carrier assembly to the base plate assembly.

6. The mortar of claim 1, the mortar carrier assembly being couplable to the mortar assembly in a manner in which the mortar assembly is capable of being layed and fired with the mortar carrier assembly coupled thereto.

7. The mortar of claim 1, the mortar carrier assembly having a container for storing and transporting attachments for the mortar assembly.

8. The mortar of claim 1, the mortar carrier assembly having at least a pair of spaced apart rails, the rails being adapted for ground contact when pulling the mortar carrier assembly coupled to the mortar assembly over the ground.

9. The mortar of claim 1, the mortar carrier assembly having at least two spaced apart, ground engaging wheels disposed on each of the rails.

10. The mortar of claim 1, the mortar carrier assembly having at least one inflatable bladder operably coupled thereto for deployment to provide buoyancy in fording a body of water.

11. A mortar earner assembly, the mortar carrier assembly being operably couplable to a mortar assembly, comprising: a unitized assembly, including in cooperation, the mortar assembly, for the ready transportation of the mortar assembly.

12. The mortar carrier assembly of claim 11, defining a cradle for supporting the mortar assembly.

13. The mortar carrier assembly of claim 1, the mortar carrier assembly effecting the removable, fixed coupling of a mortar tube assembly and a base plate assembly.

14. The mortar carrier assembly of claim 11, having a sled configuration for transporting the mortar assembly in cooperation with the mortar carrier assembly along the ground in a unitized assembly.

15. The mortar carrier assembly of claim 14, the sled configuration being defined in part within four spaced apart substantially parallel rails

16. The mortar carrier assembly of claim 11, having first and second couplings for coupling the mortal- carrier assembly to a mortar tube assembly and a third coupling for coupling the mortar carrier assembly to the base plate assembly.

17. The mortar carrier assembly of claim 11, being couplable to the mortar assembly in a manner in which the mortar assembly is capable of being layed and fired with the mortar carrier assembly coupled thereto.

18. A method of assembling a mortar into a readily transportable state, the mortar having a mortar tube assembly, a base plate assembly operably couplable to the mortar tube assembly, and a mortar mount bipod assembly operably couplable to the mortar tube assembly, the method comprising: operably coupling a mortar carrier assembly to the mortar assembly, the mortar assembly comprising the mortar tube assembly, the base plate assembly, and the mortar mount bipod assembly, in a unitized cooperative assembly for the ready transportation thereof.

19. The method of claim 18, including defining a cradle for supporting the mortar assembly.

20. The method of claim 1, including effecting a removable, fixed coupling of the mortar tube assembly and the base plate assembly.