Ricochet Firing, upon a smooth surface within certain distances, has some important advantages over direct firing. When the guns have very little or no elevation, and are near the water, as they are in a ship's battery, the projectile strikes the water at a very small angle; its flight is not greatly retarded by the graze, and it rises but little above the surface in its course. The distant charge should always be used, but the penetration is not to be depended on beyond 1,500 yards against ships-of-war.
Ricochet firing at low elevations requires only correct lateral direction, since the projectile would rarely pass over and would probably strike a vessel if within its effective range, whether the actual distance had been correctly ascertained or not.
The deviation of projectiles is, however, generally increased by ricochet, and in proportion to the roughness of the surface of the water. Even a slight ripple will make a perceptible difference not only in direction, but in range and penetration, and the height to which the projectile will rise in its bounds.
Although these facts demand attention, yet when the estimated distance does not require an elevation of more than three degrees, projectiles from guns pointed rather too low for direct firing will probably ricochet and strike the object with effect, even when the water is considerably rough. This may be called "accidental ricochet."
When the water is not smooth, the most favorable circumstances for ricochet firing are when the flight of the shot is with the roll of the sea, and that roll is long and regular.
Ricochet will be effective against small objects up to 2,000 yards, but should not commence at less than 600 yards; at less distances it is preferable to fire direct. Ricochet is of no value from rifled guns firing elongated projectiles, as they lose all certainty of direction on the rebound.
Upon smooth water, a shot fired horizontally from the 32-pdr. of 33 cwt., with 4 1/2 lbs. powder, ricocheted and rolled about 3,000 yards; the greatest range obtained from an elevation of 5°, with the same gun and charge, was less than 1,800 yards. See Dahlgren's Report on 32-pdr. of 32 cwt., p. 90.
Shot rarely ricochet at all with elevations above 5°, and the bounds are always higher, with equal charges from the same gun, as the elevation of the gun is increased.
319. Concentration of fire may be desirable under certain circumstances; and arrangements have been sometimes made to secure it by the simultaneous discharge of a number of guns upon some part of an object whose distance is known.
The advantages of these arrangements are not very obvious, excepting in cases where the position of the enemy may be visible from one part of a ship and not from all the guns in the batteries.