Method for ensuring a predetermined muzzle velocity of an artillery projectile and projectiles designed according to said method

Abstract

The present invention relates to a method in firing artillery projectiles, such as various types of shells ( 1, 26 ), from rifled barrels ( 5 a, 5 b ) for preventing the degree of wear of the barrel from which the projectiles are fired from having a negative effect on the muzzle velocity of the projectiles. The invention also encompasses a number of artillery projectiles or shells ( 1, 26 ) designed according to said method, and a method of manufacturing these. The invention encompasses a number of different variants for solving the stated problem, the basic principle of all of these variants being to adjust the band positions of the shells to the degree of barrel wear, so that a perfect propellant gas obturation is at all times obtained between the band ( 9, 11 - 14, 19 - 21, 23 and 33 ) and the origin of the rifling in the barrel, regardless of the degree of barrel wear.

1 . Method in firing artillery projectiles from rifled barrels for preventing the degree of wear of the barrel from which the projectile is fired from having a negative effect on the muzzle velocity of the projectile, characterized in that the position of the band of the projectiles or shells, used in firing, in relation to the origin of the rifling, that is to say where the barrel riffling begins, is rendered independent of the origin of the rifling in the barrel, the position of which varies according to the degree of barrel wear, in that said band position is adjusted in the longitudinal direction of the shell according to the actual position of the origin of the rifling. 
   
   
       2 . Method in firing artillery projectiles from rifled barrels according to the method in  claim 1  for preventing the degree of wear of the barrel from which the projectile is fired from having a negative effect on the muzzle velocity of the projectile, characterized in that the projectile or the shell used when loading the barrel is rammed home to a point of contact between the band of the projectile or the shell and the origin of the rifling, which is independent of the origin of the rifling in the barrel, the position of which varies according to the degree of barrel wear. 
   
   
       3 . Method according to  claim 2 , characterized in that when cartridge ammunition is used for loading the barrel the projectile is rammed home with such force that the projectile or the shell is, if necessary, already detached from the cartridge case at the time of ramming home, that is to say before its propellent charge has been ignited. 
   
   
       4 . Method in firing artillery projectiles from rifled barrels according to the method in  claim 1  for preventing the degree of wear of the barrel from which the projectile is fired from having a negative effect on the muzzle velocity of the projectile, characterized in that in firing, shells or projectiles are used which are provided with bands, the position of which in the longitudinal direction of the projectile or the shell has been adjusted to the degree of barrel wear, so that the ram-home position of the projectile or the shell in the barrel can be maintained unaltered regardless of the degree of wear of the barrel. 
   
   
       5 . Method according to  claim 4 , characterized in that in firing, projectiles are used which are provided with a forward band adjusted to heavily worn barrels and a rear band adjusted to slightly worn barrels. 
   
   
       6 . Method according to  claim 4 , characterized in that in firing, shells or projectiles are used which are provided with bands which are displaceable in their longitudinal direction and the position of which in the longitudinal direction when each is respectively rammed home is adjusted to a position that varies according to the degree of wear of the barrel. 
   
   
       7 . Method according to  claim 6 , characterized in that in firing, projectiles ( 1 ) are used which have a first band displaceable in the longitudinal direction of the projectile or the shell and adjusted to more or less worn barrels, and a second rear band fixed in the longitudinal direction of the projectile or the shell and adjusted to less worn barrels. 
   
   
       8 . Method according to  claim 7 , characterized in that in firing, shells or projectiles are used in which a ductile obturator ring is fitted between their moveable bands and fixed bands. 
   
   
       9 . Projectile or shell intended for performing the method according to  claim 1 , characterized in that it is provided with at least one band, the position of which in the longitudinal direction of the projectile or the shell has been adjusted to the degree of barrel wear, so that the ram-home position of the projectile or the shell in the barrel can be maintained unaltered regardless of the degree of wear of the barrel. 
   
   
       10 . Projectile or shell according to  claim 9 , characterized in that it is provided with a forward band adjusted to heavily worn barrels and a rear band adjusted to slightly worn barrels. 
   
   
       11 . Projectile or shell according to  claim 9 , characterized in that it is provided with at least one band displaceable in its own longitudinal direction and the position of which in the longitudinal direction when it is respectively rammed home is adjusted to a position that varies according to the degree of wear of the barrel. 
   
   
       12 . Projectile or shell according to  claim 9 , characterized in that it is provided with a first band displaceable in the longitudinal direction of the projectile or the shell and adjusted to more or less worn barrels, and a second rear band fixed in the longitudinal direction of the projectile or the shell and adjusted to less worn barrels, 
   
   
       13 . Projectile or shell according to  claim 12 , characterized in that it comprises a ductile obturator ring or third band fitted between its own moveable band and the fixed band. 
   
   
       14 . Projectile or shell intended for performing the method according to  claim 1 , characterized in that it is provided with at least one band provided with lip seals, which are angled rearwards in the firing direction of the projectile and are not too hard to be deformable in slightly worn barrels but afford obturation during the initial phase of firing in heavily worn barrels. 
   
   
       15 . Method for manufacturing banded shells designed according to  claim 9 , characterized in that the shells are made in two halves, which are screwed together, the one shell half having a threaded joint part, which in assembling is introduced into the other internally threaded shell half, once the separately manufactured band has been pressed over either of the shell halves into its intended location formed directly adjoining the joint. 
   
   
       16 . Method according to  claim 15  for manufacturing shells having at least one moveable band of the type that it is provided with at least one band, the position of which in the longitudinal direction of the projectile or the shell has been adjusted to the degree of barrel wear, so that the ram-home position of the projectile or the shell in the barrel can be maintained unaltered regardless of the degree of wear of the barrel and being provided with at least one band displaceable in its own longitudinal direction and the position of which in the longitudinal direction when it is respectively rammed home is adjusted to a position that varies according to the degree of wear of the barrel, characterized in that the band that is intended to move is pressed down over splined grooves/lands formed in either of the shell halves to its forward position in the intended firing direction (a) of the shell, following which the shell halves are screwed together. 
   
   
       17 . Projectile or shell according to  claim 10 , characterized in that it is provided with at least one band displaceable in its own longitudinal direction and the position of which in the longitudinal direction when it is respectively rammed home is adjusted to a position that varies according to the degree of wear of the barrel. 
   
   
       18 . Projectile or shell according to  claim 10 , characterized in that it is provided with a first band displaceable in the longitudinal direction of the projectile or the shell and adjusted to more or less worn barrels, and a second rear band fixed in the longitudinal direction of the projectile or the shell and adjusted to less worn barrels. 
   
   
       19 . Projectile or shell according to  claim 11 , characterized in that it is provided with a first band displaceable in the longitudinal direction of the projectile or the shell and adjusted to more or less worn barrels, and a second rear band fixed in the longitudinal direction of the projectile or the shell and adjusted to less worn barrels. 
   
   
       20 . Projectile or shell according to  claim 18 , characterized in that it comprises a ductile obturator ring or third band fitted between its own moveable band and the fixed band.