It does apply, that's just physics. There's a lot of tedious detail when you get into it, but the short version is that worn barrels have poor accuracy and can burst.I have seen a comment from an Ex USA tank person that the main effect is loss of accuracy also they have to keep a careful count of what they fire - type and number. Other sources mention worn size being measured. However if a projectile jams the barrel will split. If it's HE ?? The breaches usually seem to be reinforced to take the higher initial loads. Not really looked to see if that applies to all tanks The tanks can fire missiles as well -Russia's can so assume others can too.