Showing posts with label Projectile. Show all posts
Showing posts with label Projectile. Show all posts

Thursday, 19 May 2022

Two Piece Or Not Two Piece,That Is The Question

 
Her Majestys Ship Prince of Wales exercising with Lightnings from 207 Squadron Royal Air Force for the first time on the 9th of September 2021
 
 
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.
 
A cutaway Israel Military Industries single piece 120mm Armour Piercing Fin Stabilized Discarding Sabot cartridge showing the projectiles intrusion in to the case
 
 
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.
 
Troopers from the Queens Royal Hussars load their Challenger 2 tanks during the Strong Europe Tank Challenge at Grafenwoehr in Germany on the 7th of June 2018
 
 
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.
 

Sunday, 15 May 2022

Remember The Alamo

 
Department of Defense Fiscal Year 2022 Budget Estimates for Procurement of Intermediate Caliber Gun Ammunition
 
 
The ballistically illiterate often think that a small calibre rapid firing cannon is what is needed for engaging aerial targets,which is the opposite of the truth as smaller projectiles tend to have a longer time of flight and generate a smaller effective volume than larger ones,but to compensate for the inherent inadequacy of the 57mm Bofors 57 Mark 3 Naval Gun System there is a transformational cartridge incorporating a guidance sytem called the Advanced Low-Cost Munitions Ordnance (ALaMO),unfortunately each one costs sixteen times more than a High Explosive Point Detonating round,seven times more than a 3P Mark 295 cartridge and about five times more than a 5 inch Mark 187 High Explosive projectile with a Mark 419 Multi-Function Fuze and full propelling charge,and firing two hundred and twenty rounds per minute at a suicide boat swarm attack would cost almost one hundred thousand pounds per second.