"smooth-bore" . . . "main weapon" . . "rifled gun" . "tank use" . . . . . . . "tank cannon" . "Main gun" . . . "tank's main gun" . "Tank gun" . . . . "gun barrel" . . . "tank-mounted gun" . "armament" . . . . . "tank" . . . "Tank gun" . "cannon" . "main battle tank gun" . . "light artillery guns" . . . . . . . "main gun" . . "tanks" . . . . . . . "gun" . . . "high caliber cannons" . . . . . "tank gun" . . "main guns" . .