Cased telescoped ammunition

Abstract

 A simplified cased telescoped round (100) of ammunition utilizing a control tube (116A) for (i) a full bore projectile (122) or (ii) an APDS sabot projectile (222) (i.e., not a long rod sabot projectile), and to provide such a cased telescoped round (100) of minimalized length. A cased telescoped round (100) with a minimalized number of parts to make up the assembly and wherein the control tube (116A) is integral with the aft seal (116) and itself retains the projectile (122). A cased telescoped round (100) with an APDS sabot projectile with minimalized potential balloting and minimalized control tube (116) launch stroke length. A cased telescoped round (100) having a control tube (116A) which is integral with the aft seal (116) and itself retains the projectile (122) against loose forward movement.

Description

Field Of The Invention

[0001] This invention relates to cased telescoped ammunition utilizing a "control tube" to provide an initial forward displacement of the projectile from the case into the gun barrel prior to the subsequent ignition of the main charge which propells the projectile along the length of the gun barrel.

Background Of The Invention

[0002] Cased telescoped ammunition utilizing control tubes are well known, and are shown, for example, in:
U.S. 4,938,145, issued July 3, 1990 to W.E. Martwick;
U.S. 4,907,510, issued March 13, 1990 to W.E. Martwick, et al;
U.S. 4,846,069, issued July 11, 1989 to B.B. Tasson, et al;
U.S. 4,803,927, issued Feb. 14, 1989 to W.J. Washburn;
U.S. 4,782,758, issued Nov. 8, 1988 to W.J. Washburn;
U.S. 4,691,638, issued Sept. 8, 1987 to D.A. Meyer, et al; and
U.S. 4,604,954, issued Aug. 12, 1986 to S.E. Clarke, et al.

[0003] Cased telescoped ammunition not utilizing control tubes are also well known, and are shown, for example, in:
U.S. 3,009,394, issued Nov. 21, 1961 to E.A. Kamp, et al.

[0004] The use of sabot projectiles having fin stabilized long rod penetrators in cased telescoped ammunition is also known, as shown in U.S. 4,846,069, mentioned above. Other sabot projectiles are shown, for example, in:
U.S. 4,881,466, issued Nov. 21, 1989 to J.E. McGinley;
U.S. 4,776,280, issued Oct. 11, 1988 to J. Burri, et al;
U.S. 3,714,900, issued Feb. 6, 1973 to F.K. Feldman; and
U.S. 3,496,869, issued Feb. 24, 1970 to W. Engel.

[0005] It will be noted that the sabots are not of full bore dimension at the forward end of the sabot and penetrator assembly. It will also be noted that the use of spin stabilized penetrators in a sabot projectile in a cased telescoped round is not shown.

SUMMARY OF THE INVENTION

[0006] An object of this invention is to provide a simplified cased telescoped round of ammunition utilizing a control tube for (i) a full bore projectile or (ii) an APDS sabot projectile (i.e., not a long rod sabot projectile.)

[0007] Another object is to provide such a cased telescoped round of minimalized length.

[0008] Yet another object is to provide such a cased telescoped round with a minimalized number of parts to make up the assembly and wherein the control tube is integral with the aft seal and itself retains the projectile.

[0009] Still another object is to provide such a cased telescoped round with an APDS sabot projectile with minimalized potential balloting and minimalized control tube launch stroke length.

[0010] A feature of this invention is a cased telescoped round having a control tube which is integral with the aft seal and itself retains the projectile against loose forward movement.

BRIEF DESCRIPTION OF THE DRAWING

[0011] These and other objects, features and advantages of the invention will be apparent from the following specification thereof taken in conjunction with the accompanying drawing in which:

FIG. 1 is a longitudinal view in section of a cased telescoped round with a control tube and a full bore projectile of the prior art;

FIG. 2 is a longitudinal view in section of a cased telescoped round with a control tube and a full bore projectile in a first embodiment of the invention; and

FIG. 3 is a longitudinal view in section of a cased telescoped round with a control tube and an APDS sabot projectile in a second embodiment of the invention.

DETAILED DESCRIPTION OF THE INVENTION

[0012] Reference is first made to the prior art round shown in FIG. 1. This round 10 is comprised of a metal case 12 which is clipped to and between a front seal 14 and an aft seal 16. A control tube 18 is fixed into a longitudinal bore 20 in the aft seal. The tube 18 has an aft bore portion 22 in which is fixed a primer 24, an intermediate flash passageway 26, and a forward bore portion 28 in which is fixed a booster charge 30. An annular aft main charge 32 and an annular forward main charge 34 support these between a frangible retainer 36 which is clipped into a groove 38 in the base portion of a full bore projectile 40 (HEI, API or TP). The projectile has a piston 42 extending aftwardly from its base portion into the forward bore portion 28 of the control tube. The projectile has a rotating band 44 to provide spin stabilization. The front seal has a longitudinal bore 46 therein which will pass the projectile and which is closed by a frangible disc 48.

[0013] In operation, the primer 24 is percussed to provide ignition gas to the booster charge 30 which generates an initial volume of hot combustion gas. The gas acts against the aft surface of the piston 42 to move the projectile forwardly, fracturing the retainer 36 and the disc 48, and into the gun barrel. When the aft end of the piston exits the forward end of the control tube, the hot combustion gas from the booster vents from the tube to ignite the forward and aft main charges, which generate the main volume of combustion gas to progressively fully seat the projectile in the barrel, engrave the rotating band, and send the projectile along the length of the gun barrel and out the muzzle.

[0014] It will be appreciated that (i) the length of such a round must accomodate the length of the piston, (ii) there are many parts to assemble in fabricating the round, and (iii) the piston displaces the center of gravity of the projectile undesirably aftwards, induces parasitic aerodynamics, and makes no useful contribution of fragments when the HEI projectile impacts the target.

[0015] A much shorter and simpler round is shown in FIG. 2 as a first embodiment of the present invention. This round 100 is comprised of a case 112 (here shown as metal, but which may be nonmetallic) which is clipped to and between a front seal 114 and an aft seal 116 which also serves as a full caliber control tube and a projectile retention device. Alternatively, the case 112 may be integral with the aft seal 116. The main charge 118 is a single tube having a longitudinal bore having a forward portion with a diameter to accommodate the diameter of the rotating band 120 on the projectile 122, and an aft portion with a diameter to accommodate the diameter of the control tube portion 116A of the aft seal 116. The forward-most margin of the control tube portion has an annular crimp 124 which fits into an annular groove 126 in the projectile 122 aft of the rotating band. The aft seal 116 also has a cup 116B formed therein which receives a primer 128, and a flash passageway 130 which leads into the interior of the control tube portion which receives the booster charges 132. The annular crimp 124 is formed after the booster and the projectile have been inserted into the control tube portion in the same manner that the neck of a conventional cartridge case is crimped onto a projectile. The HEI projectile will include a fuze, which may be of the type shown in U.S. 4,242,963, issued Jan. 6, 1981 to R.T. Ziemba. The case joins the seals with snap-in features, not shown, which may be of the type shown in U.S. 4,691,638, mentioned previously. Thus, the round is made up of seven parts: projectile, primer, booster charge, main charge, aft seal, forward seal and case.

[0016] Another much shorter and simpler round is shown in FIG. 3 as a second embodiment of the present invention. The round shown here is an APDS configuration with a modification of the sabot projectile shown in U.S. 4,881,466, issued Nov. 2, 1989 to J.E. McGinley. This round 200 is comprised of a metal case 212 which is clipped to and between a front seal 214 and an aft seal 216 which also serves-as a full caliber control tube and a projectile retention device. The main charge 218 is a single tube having a longitudinal bore having a forward portion with a diameter to accommodate the rotating band 220 in the sabot foresection 222, and an aft portion with a diameter to accommodate the diameter of the control tube portion 216A of the aft seal 216. The forwardmost margin of the control tube portion has an annular crimp 224 which fits into an annular groove 226 in the sabot foresection 222 aft of the rotating band. The aft seal 216 also has a cup 216B formed therein which receives a primer 228 formed therein which receives a primer 228 and a flash passageway 230 which leads into the interior of the control tube portion which receives the booster charge 232. The sabot assembly includes a pusher 234. The sabot foresection 236 also provides a bore-rider and an integral closed front 238. The subcaliber penetrator 240 is surmounted with a windscreen 242.

[0017] The blunt-nose sabot projectile provided by the bore-rider provides two major improvements over the conventional sabot projectile: (i) the penetrator is much better supported in the barrel bore, thereby reducing balloting of the projectile and resultant dispersion, and (ii) the barrel bore is sealed sooner in the launch stroke which enables much greater flexibility in the design of the control tube launch and sequencing of the main charge ignition, i.e., the conventional problem of obturating the barrel prior to main charge ignition is eliminated. Location of the rotating band along the sabot is also flexible from the point of view of launch dynamics and may be moved forward on the projectile to allow the full-bore control tube to extend further forward. This is true for conventional and saboted projectiles. Obviously, constraints on sabot strength and transmission of rotational loads for spin-up must also be considered in band location.

Claims

1. A cased telescoped round of ammunition comprising:
   a front seal;
   an aft seal;
   a projectile; and
   a control tube which is integral with said aft seal and which interengages with said projectile to retain said projectile against forward movement.

2. A cased telescoped round of ammunition comprising:
   a projectile having a full bore body;
   an aft seal having a control tube which interengages with said full bore body of said projectile to retain said projectile against forward movement.

3. A round according to claim 2 wherein:
   said projectile body has an annular groove; and
   said tube has an annular detent which is seated in said groove.

4. A round according to claim 2 wherein:
   said projectile body includes a sabot having an annular groove; and
   said tube has an annular detent which is seated in said groove.

5. A round according to claim 2 wherein:
   said aft seal supports a primer at the aft end of said round and said tube contains a booster between said primer and said projectile.

6. A round according to claim 4 wherein:
   said sabot has a rotating band and a forward bore rider.

7. A round according to claim 4 wherein:
   said sabot has a front end which is formed as a right cylinder having a full bore diameter.

8. A round according to claim 2 wherein:
   said projectile body includes
      a penetrator, and
      a sabot which completely encloses said penetrator.

Drawing