Short Take Off and Vertical Landing naval aircraft have never generated higher sortie rates in combat than conventional aircraft,and logic suggests they never shall as they spend more time undergoing maintenance due to their complex vertical lift systems,but on some British websites it has become a matter of lore that they do,as has the idea that American Abrams Main Battle Tanks cost less than the United Kingdom's Challengers,that Black Hawk helicopters cost less than Wildcats,and that small calibre guns are better at engaging aircraft than large ones,some even think tank guns with single piece ammunition are better than those with two piece ammunition and that shall be the subject of our lesson for today.
Longer kinetic energy projectiles are better at penetrating armour than short ones,but the charge and projectile of single piece cartridges are stored in series with each other and the Cartridge Over All Length is constrained by the length of the space in which it is stored which means that a longer projectile must intrude further in to the cartridge case and must be shorter than the overall length,and the longer it is the more chamber volume it consumes leaving less space for propellant and therefore reducing muzzle velocity,which is a significant disadvantage.
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The length of two piece ammunition is also constrained by the available storage space,but as the charge and projectile are in series only when loaded in to the gun (at which point there is no restriction on over all length because the barrel has a hole at the other end),the projectile can occupy the entire length of the available storage space and therefore can be longer than the projectile of a single piece cartridge,without intruding in to the chamber,leaving more volume available for propellant and thereby increasing muzzle velocity,which is a significant advantage.
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