AS90 is a 155mm self-propelled gun that equips six Field Regiments of the Royal Horse Artillery and Royal Artillery. Fitted with a standard barrel, AS90 can fire the NATO L15 unassisted 155mm projectile (96lbs) 24.7 km. With a long (52 Calibre) barrel the gun can reach out to 30 km using standard ammunition, and 60-80 km with Extended Range
Can't fully answer that one. AS implies some sort of artillery I recall, so it's range should be beyond maybe 8 miles perhaps. The 90 wouldn't be the caliber, more the composition of or the charge or the warhead. Probably a conventional shell, meant for structural demolition. Getting rusty on military facts.