Abstract:
A gun system has a two piece cannon assembly that is separated between a removable chamber instead of a traditional breech, and a projectile forcing cone. The chamber has a plug at one end that can accommodate any type of ignition system, and the other end is open and is attached to the barrel with a connection fitting. High pressure gases created by combustion of the propellant are sealed with a high-pressure gas compression seal at the interface between the chamber and the barrel. The connection fitting provides an attachment for a rear cannon bearing slide, which rides on rails attached to the main support structure, and also reacts any torque induced into the barrel from the actuation of the chamber/barrel locking collar. A turntable upon which are mounted two chamber elevating/support mechanisms and two projectile loader/rammer mechanisms is positioned around one of the main support structure legs.

Description:
This relates to U.S. Provisional Application 60/251,349 filed on Dec. 4, 2000. This invention pertains to long range artillery, and more particularly to artillery having a low profile and improved performance. 
    
    
     BACKGROUND OF THE INVENTION 
     There is a resurgence of interest in the US Navy in long range artillery as a replacement for missiles due to the cost savings involved. That is, even though the missile launcher is normally cheaper than a gun of similar caliber, each missile is much more expensive than the projectile and propellant for the gun and this soon outweighs the extra cost of the gun system. 
     To obtain greater range, the gun barrels must be longer or the chamber pressure must be greater. A combination of these two factors, together with optimum projectile design, provides the best opportunity for long range firings. However, the protrusion of the barrel above the deck is vulnerable to detection by enemy radar, hence it is of interest to reduce this to a minimum. 
     To maximize the length of barrel for a given protrusion of the barrel from the housing module, there should be a minimum of recoiled components behind the chamber/breech, and also, the recoil stroke should be as short as possible. The optimum space utilization is to have only enough room behind the back of the cannon assembly for recoiling. For this to be effected, the chamber must be separated from the barrel to allow for loading of the projectile and charge. This also allows a reduction in time between shots as the charge may be loaded at the same time as the projectile. 
     The gun described herein embodies the necessary features to allow for compact stowage as well as providing improved performance. A 5 inch caliber smooth bore barrel has been assumed, however the design can be readily scaled up or down. 
     SUMMARY OF THE INVENTION 
     The invention provides a gun system that incorporates a two piece cannon assembly that is separated between the chamber and the projectile forcing cone. The gun described has no traditional breech. It has a removable chamber instead which has a plug at one end that can accommodate any type of ignition system that may be required. The other end is open and is attached to the barrel with a connection fitting that is clamped to the barrel by a threaded collar. The high pressure gases created by the propellant combustion are sealed with a high-pressure gas compression seal at the interface between the chamber and the barrel. The lower side of the connection fitting has a locking collar screwed into it. The internal diameter of this locking collar has a bayonet feature or interrupted thread to suit the top end of the chamber. A torque plate, which extends out beyond the edge of the connection fitting, is attached to the lower face of the collar. A slot in the torque plate aligns with the pin of a slide actuator that is attached to a frame cross-member. When the cannon assembly is in battery position, the actuator pin is located inside the torque plate slot. 
     The connection fitting also provides the attachment for the rear cannon bearing slide which rides on rails attached to the main support structure. This also reacts any torque induced into the barrel from the actuation of the chamber/barrel locking collar. 
     To provide adequate clearance to the loading mechanism, the recoil cylinders are mounted in front of (above) the chamber/barrel connection fitting. The lower end of the cylinders are attached to the connection fitting. The structure necessary to support the front of the recoil cylinders and hence transmit the recoil force to the main support, provides a suitable mounting for the front barrel slide. The resultant extended “wheelbase” between the front and rear slides ensures improved shot repeatability. 
     A turntable upon which are mounted two chamber elevating/support mechanisms and two projectile loader/rammer mechanisms is positioned around one of the main support structure legs. 
    
    
     DESCRIPTION OF THE DRAWINGS 
     The invention and its many attendant objects and advantages will become more clear upon reading the following description of the preferred embodiment in conjunction with a review of the following drawings, wherein: 
     FIG. 1 is a perspective view of a gun assembly according to this invention; 
     FIG. 2 is a sectional side elevation of the gun assembly shown in FIG. 1; 
     FIG. 3 is a sectional front elevation of the gun assembly shown in FIG. 1; 
     FIG. 4 is an enlarged sectional elevation of the circled area shown in FIG. 2; 
     FIG. 5 is an enlarged sectional elevation of the circled area in FIG. 3; 
     FIG. 6 is an enlarged sectional elevation of the circled area in FIG. 4; 
     FIG. 7 is a sectional plan view along lines  7 — 7  in FIG. 3; 
     FIG. 8 is a sectional plan view along lines  8 — 8  in FIG. 3; 
     FIG. 9 is a sectional elevation of a recoil cylinder and an attached hydraulic schematic diagram of recoil energy recovery system; 
     FIG. 10 is a sectional elevation of a recoil cylinder configured to provided a self contained counterrecoil force; and 
     FIG. 11 is an elevation of the barrel shown in FIG. 1 with the barrel sleeve removed to show cooling channels. 
    
    
     DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT 
     Turning now to the drawings, wherein like reference characters identify identical or corresponding parts, and more particularly to FIGS. 1-3 thereof, a long range artillery cannon  30  is shown having an elongated barrel  32  mounted in a recoil mechanism  34  attached to a main support structure  36  over a chamber shuttle turntable system  38 . 
     The main support structure  36  includes two legs  40  and a cross head  42  attached to the front or upper end of the legs  40 . The cross head  42  has a central axial opening  44  that receives and guides the barrel  32  during the axial movement of recoil and recovery to battery position. The underside of the cross head  42  has a pair of lugs  46  for connection to the upper ends of piston rods  48  operation in cylinders  49  of the recoil mechanism  34 , as described in more detail below. 
     The chamber shuttle turntable system  38  has a turntable  50  that rotates around one of the support structure legs  40 , providing two functions. It supports the mechanisms  51  that locate and elevate the two chambers  52  and it also supports the rammer/loader mechanisms  55  that ram projectiles  58  into the barrel. It rotates at the appropriate time of the firing cycle to align a chamber  52  or a loader/rammer  55  with the rear of the barrel. 
     The attachment of a chamber  52  to the barrel is by means of a rotating locking collar  60  that is screwed into a rear barrel fitting  62  and locates the end of the chamber  52  with either a six-part segmented bayonet connection or interrupted grooves. The preferred configuration is with the interrupted grooves (see FIG. 4) as it provides a more even load distribution along the length of the connection and is more compact. It is rotated through the 30° necessary to fully connect by means of hydraulic cylinders  65  acting tangentially (see FIG.  7 ). At the same time, axial force is maintained on the chamber by the lifting cylinders  68  (see FIG. 5) to ensure adequate seating of a high pressure seal  70  (see FIG.  6 ). The hydraulic cylinders  65  that rotate the locking collar  60  are mounted to the static support structure and apply force to the collar  60  by means of a sliding pin  72  engaging with a slot in a torque plate  75  which is attached to the collar  60  (see FIG.  4 ). During recoil, the pin  72  (which is non-recoiling) disengages from the slot in the torque plate  75  (which is recoiling) and then re-engages when the barrel returns to battery position. The chamber  52  is disengaged by reversing the above operations. 
     Sealing of Chamber Section to Barrel 
     The chamber  52  is designed to be loaded with a rigid combustible propellant charge case  78  incorporating the metallic high pressure sealing ring  70  clipped or molded into its down range end (see FIG.  6 ). This sealing ring is therefore replaced at each shot. The sealing function is performed in two ways. The primary method of sealing is via the stub cartridge case thin wall sleeve design at each end of the ring which expands under the effect of the rising gas pressure to contact the barrel/chamber wall during firing. The secondary (back-up) method is via the conical sections of the ring which are compressed during the barrel/chamber connection to produce a seal/tube interface pressure sufficient to seal the gas pressure prior to it rising and energizing the seal. The forward extension of the seal ring also protects the conical barrel surface where the chamber diameter transitions down to the bore diameter and where the potential for gas erosion is at the maximum. 
     The geometry of the seal  70 , chamber  52  and barrel  32  are selected to ensure the seal  70  stays in the chamber when it is separated from the barrel. Prior to installing a new propelling charge, the old sealing ring  70  is removed and stored or discarded (the remainder of the propellant charge, including the case, having been fully consumed). The design of the sealing ring  70  facilitates easy removal after firing by means of a mechanical claw extractor being inserted into it and then expanded to lock in place. Incorporated with the extractor may be a compressed air supply to blow any dirt particles from the barrel/chamber sealing surfaces prior to insertion of the replacement charge. 
     Turntable 
     The turntable  50  is shown in FIGS. 7 &amp; 8. The descriptions of the two types of mechanisms mounted to the turntable  50  are as follows: 
     Turntable chamber elevating/support—There are two alternatives for this attachment and these are as follows: 
     Alternative 1) A rotating locking collar in the rear barrel fitting-chamber does not rotate. The chamber  52  is located in the elevating/support mechanisms  51  in a non-rotating sliding sleeve  80  which supports it in between shots as well as guides it whilst being raised by hydraulic cylinders to mate with the rear face of the barrel. At the base of the chamber are castellated features  82 . At the base of the sliding sleeve is a rotating support ring which has a castellated internal diameter and is hydraulically actuated. The chamber castellations rest on the ring castellations whilst the chamber is being raised into position or is in the rest position between shots. After the chamber is attached to the barrel by means of the locking collar, the support ring is rotated such that the castellations are now out of phase with each other, thereby allowing the chamber clearance to recoil through the ring. 
     Alternative 2) The chamber section is rotated. An alternative method of effecting the connection between the chamber and the barrel is to directly mate the chamber to the connection fitting, instead of via a locking ring, by means of bayonet features or interrupted threads. The joint is then tightened by rotating the chamber. The high pressure seal may be compressed by either the action of the chamber torque resulting in axial force via the interrupted threads or helical profile on the bayonet interface, or more directly, by the hydraulic cylinders which raise and lower the chamber. The disadvantage of this method is that the acceleration/deceleration forces involved in rotating a heavy object such as the chamber requires additional support structure, energy input and time. This may be objectionable for high firing rates. 
     Turntable projectile loader/rammer—Projectiles are introduced into a support tube  84  of the loader/rammer  55  by means of a handling system (not described herein). Parallel to and alongside the support tube is a hydraulic cylinder  86  that has an arm  88  extending under the projectile base. This causes the projectile to be rammed into the lower end of the barrel such that a seal  90  on the projectile  58  is compressed into the barrel forcing cone. This keeps the projectile  58  from falling back down into the support tube when the loader/rammer  55  is withdrawn. 
     Cooling 
     The gun described herein has been designed with integrated active cooling. This is not a requirement of the overall design but does permit higher rates of fire by removing the heat from the areas where it is mainly generated, i.e., the barrel  32 , the chamber  52 , and recoil cylinders. The sketches show a thin wall sleeve  92  shrunk fitted around the barrel  32 . The barrel has axial grooves  95  machined in its exterior (see FIG.  11 ). The assembly of the sleeve to the barrel creates passageways that contain the cooling fluid. The front barrel slide acts as the interface at which the cooling fluid is introduced and evacuated from the barrel. 
     Due to the fact that the chamber  52  is passed from one support medium to another, a continuous cooling fluid connection cannot be maintained to it. Hence coolant only flows when the chamber has been returned to its mount on the turntable and interfaces with the coolant connections (see FIGS.  5  and  7 ). The duration which coolant flows to the chamber is slightly less than two shots. 
     The recoil cylinders  49  can either be wrapped with cooling jackets or, in the case of the energy recovery configuration, the fluid can be cooled during its passage to the external accumulators as described below. 
     Recoil 
     The most efficient and most common method of absorbing recoil energy is via the throttling of hydraulic fluid. Traditional recoil cylinder configurations can be adapted to function satisfactorily. However, if a traditional recoil cylinder is used, a counterrecoil cylinder is also required to return the gun to the battery position. 
     The following configuration has a counterrecoil as well as a recoil function and also provides the ability to extract hydraulic fluid energy from the recoil stroke which can be used to supplement overall system energy requirements to power functions such as breech locking and ammunition loading mechanism actuation. Where it is used for energy recovery, the removal of fluid during each recoil cycle also facilitates cooling via a heat exchanger. The fluid which has been heated by absorbing recoil energy is replaced with cool fluid from an external low pressure accumulator for each shot (see explanation below and hydraulic schematic). The recoil cylinder design and the hydraulic schematic for energy recovery is shown in FIG.  9 . Counterrecoil snubbing can be easily incorporated internally into this cylinder design. 
     Recoil energy recovery—The recoil cylinder  49  can be configured, together with an external high-pressure accumulator  97  and low pressure accumulator  99 , to recover hydraulic energy. During recoil, the barrel&#39;s imparted energy is absorbed by the throttling of the hydraulic fluid through the varying orifice produced between the outside of a recoil piston  100  and the bore of the cylinder extension  102 . The diameter of the bore  104  is varied along length thereof to ensure a constant and hence a minimum recoil force. This fluid is then forced through a check valve  106  where some energy is also absorbed by the compression of the nitrogen gas behind a floating piston  108  in the energy recovery accumulator inside the piston  100 . This gas volume is supplemented by an exterior gas cylinder  110  to minimize the gas pressure increase when it is compressed by the displaced recoil fluid. After recoil, stored energy, in the form of the pressurized fluid is transferred from the energy recovery accumulator to the high-pressure external accumulator  97 . Should this accumulator be fully charged, surplus fluid is dumped to the low pressure accumulator  99  via a bypass valve. The low-pressure external accumulator also provides the fluid pressure required to produce the retraction force in the cylinder to return the system to battery position. A high-pressure boost pump  112  is incorporated in the circuit to make up the difference between the hydraulic energy required for operation of all the systems and that which is supplied by the energy recovery. Pressure transducers  114  are placed appropriately in the system to ensure fail safe operation. 
     No energy recovery—Should energy recovery not be required, the recoil cylinder can also be simply configured to provided a self contained counterrecoil force using the integral floating piston  100  and compressed gas to retract the cylinder after recoiling—see FIG.  10 . After recoiling as described above, the compressed fluid passes back to the recoil chamber past the check valve and piston via an orifice. This produces the retraction force in the cylinder required to return the system to battery position. Cooling can be provided by an external water jacket around the cylinder. 
     In both cases, the cylinder rod  48  is attached to the gun support structure  42  and the cylinder  49  is attached to the recoiling components. This facilitates connections from the recoil piston to the exterior components for the two oil lines and one gas line necessary per cylinder and also permits bleeding of the system at the highest point. 
     The design of the recoil cylinder incorporates common existing technology and can therefore be designed for reliability. Also, the attachments to the support structure provide for very simple and quick replacement. 
     Stowage 
     Weapon stowage may be simply compacted by retracting the barrel the full recoil distance. This is achieved by pumping fluid out of the recoil cylinder and into a separate storage volume. Further retraction is possible by either a longer recoil cylinder or detachment of the recoil cylinder at one end and a separate system to raise and lower the weapon. In this case the chamber is detached from the barrel in the normal manner and the carousel rotated to an intermediate position to allow for clearance of the rear barrel connection fitting when retracted. 
     Maintenance 
     The most common major maintenance item is replacement of the barrel after it has developed unacceptable wear. Replacement is a relatively simple process, involving the removal of the front bearing slide and unscrewing the threaded retaining ring at the breech end. The tube can then be withdrawn through the hole in the front support structure. 
     Features, Advantages and Benefits 
     
       
         
               
               
               
             
               
               
               
               
               
               
             
           
               
                   
               
               
                 Features 
                 Advantages 
                 Benefits 
               
               
                   
               
             
             
               
                   
               
             
          
           
               
                 1.0 
                 The cannon is 
                 1.1 
                 The length of 
                 1.1.1 
                 Manufacturing - 
               
               
                   
                 separated between 
                   
                 barrel becomes 
                   
                 This assists the 
               
               
                   
                 the chamber and 
                   
                 shorter for a 
                   
                 manufacturing 
               
               
                   
                 projectile seat. 
                   
                 given cannon 
                   
                 process in a 
               
               
                   
                   
                   
                 assembly length. 
                   
                 number of ways. 
               
               
                   
                   
                   
                   
                   
                 During 
               
               
                   
                   
                   
                   
                   
                 manufacture, the 
               
               
                   
                   
                   
                   
                   
                 difficulty is 
               
               
                   
                   
                   
                   
                   
                 increased as the 
               
               
                   
                   
                   
                   
                   
                 length of 
               
               
                   
                   
                   
                   
                   
                 component 
               
               
                   
                   
                   
                   
                   
                 increases. This 
               
               
                   
                   
                   
                   
                   
                 applies to the 
               
               
                   
                   
                   
                   
                   
                 forging, heat 
               
               
                   
                   
                   
                   
                   
                 treatment, 
               
               
                   
                   
                   
                   
                   
                 exterior 
               
               
                   
                   
                   
                   
                   
                 machining, 
               
               
                   
                   
                   
                   
                   
                 interior boring 
               
               
                   
                   
                   
                   
                   
                 and autofrettage 
               
               
                   
                   
                   
                   
                   
                 processes. A 
               
               
                   
                   
                   
                   
                   
                 shorter barrel 
               
               
                   
                   
                   
                   
                   
                 would reduce 
               
               
                   
                   
                   
                   
                   
                 manufacturing 
               
               
                   
                   
                   
                   
                   
                 costs by 
               
               
                   
                   
                   
                   
                   
                 permitting 
               
               
                   
                   
                   
                   
                   
                 simpler 
               
               
                   
                   
                   
                   
                   
                 manufacturing 
               
               
                   
                   
                   
                   
                   
                 techniques. 
               
               
                   
                   
                   
                   
                 1.1.2 
                 Transportation - 
               
               
                   
                   
                   
                   
                   
                 A shorter barrel 
               
               
                   
                   
                   
                   
                   
                 permits trans- 
               
               
                   
                   
                   
                   
                   
                 portation of all 
               
               
                   
                   
                   
                   
                   
                 components in a 
               
               
                   
                   
                   
                   
                   
                 shorter container, 
               
               
                   
                   
                   
                   
                   
                 allowing deploy- 
               
               
                   
                   
                   
                   
                   
                 ment by smaller 
               
               
                   
                   
                   
                   
                   
                 vehicles/vessels. 
               
               
                   
                   
                   
                   
                 1.1.3 
                 Stowage - The 
               
               
                   
                   
                   
                   
                   
                 barrel may be 
               
               
                   
                   
                   
                   
                   
                 retracted during 
               
               
                   
                   
                   
                   
                   
                 stowage down to 
               
               
                   
                   
                   
                   
                   
                 the level of the 
               
               
                   
                   
                   
                   
                   
                 chamber inter- 
               
               
                   
                   
                   
                   
                   
                 face, thereby 
               
               
                   
                   
                   
                   
                   
                 reducing radar 
               
               
                   
                   
                   
                   
                   
                 signature. 
               
               
                   
                   
                   
                   
                   
                 Alternatively, 
               
               
                   
                   
                   
                   
                   
                 with the chamber 
               
               
                   
                   
                   
                   
                   
                 moved aside, the 
               
               
                   
                   
                   
                   
                   
                 barrel may be 
               
               
                   
                   
                   
                   
                   
                 retracted down to 
               
               
                   
                   
                   
                   
                   
                 the level of the 
               
               
                   
                   
                   
                   
                   
                 base of the gun 
               
               
                   
                   
                   
                   
                   
                 mount area, 
               
               
                   
                   
                   
                   
                   
                 further 
               
               
                   
                   
                   
                   
                   
                 reducing radar 
               
               
                   
                   
                   
                   
                   
                 signature. 
               
               
                   
                   
                 1.2 
                 Easy access to 
                 1.2.1 
                 Cleaning - Easier 
               
               
                   
                   
                   
                 the forcing cone 
                   
                 cleaning, and 
               
               
                   
                   
                   
                 area. 
                   
                 inspection of the 
               
               
                   
                   
                   
                   
                   
                 seal area during 
               
               
                   
                   
                   
                   
                   
                 operation. 
               
               
                   
                   
                   
                   
                 1.2.2 
                 Cooling - 
               
               
                   
                   
                   
                   
                   
                 Forced-air 
               
               
                   
                   
                   
                   
                   
                 cooling is 
               
               
                   
                   
                   
                   
                   
                 possible of both 
               
               
                   
                   
                   
                   
                   
                 the chamber and 
               
               
                   
                   
                   
                   
                   
                 forcing cone 
               
               
                   
                   
                   
                   
                   
                 areas. 
               
               
                   
                   
                 1.3 
                 A separate 
                 1.3.1 
                 Flexibility - 
               
               
                   
                   
                   
                 chamber and 
                   
                 This enables 
               
               
                   
                   
                   
                 barrel permits 
                   
                 many different 
               
               
                   
                   
                   
                 many variations 
                   
                 projectile/ 
               
               
                   
                   
                   
                 of each to be 
                   
                 propellant 
               
               
                   
                   
                   
                 fitted to the 
                   
                 combinations to 
               
               
                   
                   
                   
                 same mount. 
                   
                 be fired. 
               
               
                   
                   
                   
                   
                 1.3.2 
                 Optimum material 
               
               
                   
                   
                   
                   
                   
                 selection - The 
               
               
                   
                   
                   
                   
                   
                 material used in 
               
               
                   
                   
                   
                   
                   
                 the manufacture 
               
               
                   
                   
                   
                   
                   
                 of a separate 
               
               
                   
                   
                   
                   
                   
                 barrel and 
               
               
                   
                   
                   
                   
                   
                 chamber can be 
               
               
                   
                   
                   
                   
                   
                 different and 
               
               
                   
                   
                   
                   
                   
                 specifically 
               
               
                   
                   
                   
                   
                   
                 selected to 
               
               
                   
                   
                   
                   
                   
                 suit their 
               
               
                   
                   
                   
                   
                   
                 particular 
               
               
                   
                   
                   
                   
                   
                 operational 
               
               
                   
                   
                   
                   
                   
                 requirements. 
               
               
                   
                   
                 1.4 
                 A separate barrel 
                 1.4.1 
                 Wear specific 
               
               
                   
                   
                   
                 allows for easy 
                   
                 components - The 
               
               
                   
                   
                   
                 replacement 
                   
                 barrel is the 
               
               
                   
                   
                   
                 during service. 
                   
                 primary part of a 
               
               
                   
                   
                   
                   
                   
                 gun that suffers 
               
               
                   
                   
                   
                   
                   
                 from wear. 
               
               
                   
                   
                   
                   
                   
                 The majority of 
               
               
                   
                   
                   
                   
                   
                 the other 
               
               
                   
                   
                   
                   
                   
                 components are 
               
               
                   
                   
                   
                   
                   
                 not replaced until 
               
               
                   
                   
                   
                   
                   
                 their fatigue lives 
               
               
                   
                   
                   
                   
                   
                 are reached. 
               
               
                   
                   
                   
                   
                 1.4.2 
                 Time saving - 
               
               
                   
                   
                   
                   
                   
                 Simplifying 
               
               
                   
                   
                   
                   
                   
                 replacement 
               
               
                   
                   
                   
                   
                   
                 reduces time out 
               
               
                   
                   
                   
                   
                   
                 of commission. 
               
               
                 2.0 
                 The chamber and 
                 2.1 
                 This allows 
                 2.1.1 
                 Compressed time 
               
               
                   
                 projectile loader/ 
                   
                 simultaneous 
                   
                 budget - The gun 
               
               
                   
                 rammer are 
                   
                 loading of 
                   
                 can be fired at a 
               
               
                   
                 duplicated and 
                   
                 propellant in one 
                   
                 higher rate as it 
               
               
                   
                 positioned on a 
                   
                 chamber while 
                   
                 permits parallel 
               
               
                   
                 turntable such 
                   
                 the other is 
                   
                 functioning. Ie., 
               
               
                   
                 that each of the 
                   
                 being attached to 
                   
                 The used metallic 
               
               
                   
                 chambers and 
                   
                 the gun for firing. 
                   
                 gas seal can be 
               
               
                   
                 each of the 
                   
                 This also applies 
                   
                 removed and the 
               
               
                   
                 loader/rammers 
                   
                 to the two 
                   
                 next round of 
               
               
                   
                 align with the 
                   
                 rammer/loader 
                   
                 propellant can be 
               
               
                   
                 barrel when the 
                   
                 stations that are 
                   
                 loaded into one 
               
               
                   
                 turntable is 
                   
                 positioned in 
                   
                 chamber while 
               
               
                   
                 indexed. 
                   
                 between the two 
                   
                 the other is being 
               
               
                   
                   
                   
                 chamber mounts. 
                   
                 attached to the 
               
               
                   
                   
                   
                   
                   
                 rear of the barrel. 
               
               
                   
                   
                   
                   
                   
                 Also, the next 
               
               
                   
                   
                   
                   
                   
                 projectile can 
               
               
                   
                   
                   
                   
                   
                 be positioned in 
               
               
                   
                   
                   
                   
                   
                 the loader/rammer 
               
               
                   
                   
                   
                   
                   
                 at the same time 
               
               
                   
                   
                   
                   
                   
                 as the other is 
               
               
                   
                   
                   
                   
                   
                 rammed, etc. 
               
               
                   
                   
                   
                   
                 2.2.2 
                 Fault bypass - 
               
               
                   
                   
                   
                   
                   
                 Should a fault 
               
               
                   
                   
                   
                   
                   
                 occur in any one 
               
               
                   
                   
                   
                   
                   
                 of the two 
               
               
                   
                   
                   
                   
                   
                 projectile 
               
               
                   
                   
                   
                   
                   
                 rammer/loaders or 
               
               
                   
                   
                   
                   
                   
                 chamber stations, 
               
               
                   
                   
                   
                   
                   
                 the gun can 
               
               
                   
                   
                   
                   
                   
                 continue firing 
               
               
                   
                   
                   
                   
                   
                 (albeit at a lower 
               
               
                   
                   
                   
                   
                   
                 rate) using the 
               
               
                   
                   
                   
                   
                   
                 remaining func- 
               
               
                   
                   
                   
                   
                   
                 tioning station. 
               
               
                   
                   
                   
                   
                 2.2.3 
                 Facilitate 
               
               
                   
                   
                   
                   
                   
                 cooling - The 
               
               
                   
                   
                   
                   
                   
                 chamber has 
               
               
                   
                   
                   
                   
                   
                 additional time 
               
               
                   
                   
                   
                   
                   
                 to cool in 
               
               
                   
                   
                   
                   
                   
                 between shots. 
               
               
                 3.0 
                 The connection 
                 3.1 
                 Protects transition 
                 3.1.1 
                 Increased barrel 
               
               
                   
                 between the 
                   
                 area between 
                   
                 life. 
               
               
                   
                 chamber and 
                   
                 chamber and 
                 3.2.1 
                 Reduced handling 
               
               
                   
                 barrel is protected 
                   
                 forcing cone from 
                   
                 requirements 
               
               
                   
                 by a short 
                   
                 effects of 
                   
                 when removing 
               
               
                   
                 metallic sleeve/ 
                   
                 propellant gas 
                   
                 after shot. 
               
               
                   
                 seal. This is 
                 3.2 
                 Smaller than 
                 3.3.1 
                 More compact - 
               
               
                   
                 attached to the 
                   
                 cartridge case 
                   
                 A large diameter 
               
               
                   
                 rigid combustible 
                 3.3 
                 Permits a larger 
                   
                 chamber is bene- 
               
               
                   
                 cartridge case and 
                   
                 ratio of chamber 
                   
                 ficial as it reduces 
               
               
                   
                 is hence replaced 
                   
                 diameter to 
                   
                 the chamber 
               
               
                   
                 with each shot. 
                   
                 projectile 
                   
                 length for a given 
               
               
                   
                   
                   
                 diameter (the 
                   
                 volume, thereby 
               
               
                   
                   
                   
                 erosion effects 
                   
                 reducing the 
               
               
                   
                   
                   
                 in the transition 
                   
                 overall length of 
               
               
                   
                   
                   
                 area from 
                   
                 the gun. This in 
               
               
                   
                   
                   
                 propellant gas 
                   
                 turn reduces the 
               
               
                   
                   
                   
                 become more 
                   
                 amount of barrel 
               
               
                   
                   
                   
                 destructive as the 
                   
                 protrusion above 
               
               
                   
                   
                   
                 ratio increases). 
                   
                 deck. 
               
               
                   
                   
                   
                   
                 3.3.2 
                 Safer ignition - 
               
               
                   
                   
                   
                   
                   
                 Simplifies 
               
               
                   
                   
                   
                   
                   
                 obtaining efficient 
               
               
                   
                   
                   
                   
                   
                 and safe 
               
               
                   
                   
                   
                   
                   
                 propellant 
               
               
                   
                   
                   
                   
                   
                 ignition. 
               
               
                   
                   
                   
                   
                   
                 As the ratio of 
               
               
                   
                   
                   
                   
                   
                 L/D increases, so 
               
               
                   
                   
                   
                   
                   
                 does the difficulty 
               
               
                   
                   
                   
                   
                   
                 in ensuring even 
               
               
                   
                   
                   
                   
                   
                 ignition of the 
               
               
                   
                   
                   
                   
                   
                 propellant. 
               
               
                 4.0 
                 Accessible recoil 
                 4.1 
                 Easily replaceable 
                 4.1.1 
                 Time saving - 
               
               
                   
                 cylinders 
                   
                   
                   
                 Out of 
               
               
                   
                   
                   
                   
                   
                 commission time 
               
               
                   
                   
                   
                   
                   
                 reduced. 
               
               
                   
                   
                   
                   
                 4.1.2 
                 Performance 
               
               
                   
                   
                   
                   
                   
                 matching - 
               
               
                   
                   
                   
                   
                   
                 Different recoil 
               
               
                   
                   
                   
                   
                   
                 characteristics 
               
               
                   
                   
                   
                   
                   
                 may be incor- 
               
               
                   
                   
                   
                   
                   
                 porated for 
               
               
                   
                   
                   
                   
                   
                 different barrel/ 
               
               
                   
                   
                   
                   
                   
                 chamber 
               
               
                   
                   
                   
                   
                   
                 combinations. 
               
               
                   
               
             
          
         
       
     
     Method of Operation 
     The configuration of the gun with the turntable mounted chambers and loader/rammers permits some operations to be done in parallel. This facilitates a faster firing rate. The following table clarifies the operations during one complete firing cycle, starting from the recoil stroke. 
     
       
         
               
               
               
             
           
               
                   
               
               
                   
                   
                 OPERATIONS DONE 
               
               
                 OP # 
                 FIRING CYCLE TIME BUDGET (GUN) 
                 IN PARALLEL 
               
               
                   
               
             
             
               
                 1 
                 RECOIL 
                   
               
               
                 2 
                 COUNTERRECOIL 
               
               
                 3 
                 ROTATE CHAMBER SUPPORT RING 
               
               
                   
                 TO SUPPORT POSITION 
               
               
                 4 
                 UNLOAD CHAMBER #1 LOCK RING 
               
               
                 5 
                 UNLOCK CHAMBER #1 FROM 
               
               
                   
                 BARREL 
               
               
                 6 
                 LOWER CHAMBER #1 
               
               
                 7 
                 ROTATE CAROUSEL TO PROJECTILE 
                 CONNECT COOL- 
               
               
                   
                 LOAD POSITION 
                 ING TO CHAMBER 
               
               
                   
                   
                 #1 
               
               
                 8 
                 RAM PROJECTILE INTO BARREL 
                 REMOVE 
               
               
                   
                   
                 CHAMBER #1 
               
               
                   
                   
                 SEAL &amp; CLEAN 
               
               
                 9 
                 RETRACT RAMMER 
                 DISCONNECT 
               
               
                   
                   
                 COOLING TO 
               
               
                   
                   
                 CHAMBER #2 
               
               
                 10  
                 ROTATE CAROUSEL 
               
               
                   
                 TO PROPELLANT 
               
               
                   
                 LOAD POSITION 
               
               
                 11  
                 RAISE CHAMBER #2 TO BARREL 
                 REPLENISH 
               
               
                   
                   
                 CHAMBER #1 &amp; 
               
               
                   
                   
                 PROJECTILE TUBE 
               
               
                 12  
                 LOCK CHAMBER #2 TO BARREL 
               
               
                 13  
                 UNLOAD CHAMBER #2 
               
               
                   
                 SUPPORT RING 
               
               
                 14  
                 ROTATE SUPPORT RING TO RECOIL 
               
               
                   
                 POSITION 
               
               
                 15  
                 FIRE 
               
               
                   
               
             
          
         
       
     
     Obviously, numerous modifications and variations of the preferred embodiment described above are possible and will become apparent to those skilled in the art in light of this specification. Moreover, many functions and advantages are described for the preferred embodiment, but in many uses of the invention, not all of these functions and advantages would be needed. Therefore, we contemplate the use of the invention using fewer than the complete set of noted features, process steps, benefits, functions and advantages. Moreover, several species and embodiments of the invention are disclosed herein, but not all are specifically claimed, although all are covered by generic claims. Nevertheless, it is our intention that each and every one of these species and embodiments, and the equivalents thereof, be encompassed and protected within the scope of the following claims, and no dedication to the public is intended by virtue of the lack of claims specific to any individual species. Accordingly, it is expressly intended that all these embodiments, species, modifications and variations, and the equivalents thereof, in all their combinations, are to be considered within the spirit and scope of the invention as defined in the following claims, wherein