Diving Shot - Using Shots

Using Shots

The shot is deployed, generally from a boat, after the dive site is located using position fixing such as GPS and an echo sounder.

Shots are more difficult to use in strong currents. The weight may drag along the seabed especially if the divers pull on the line as they descend. To avoid this the shot is often positioned upstream of an obstruction at the dive site so the obstruction prevents it dragging. A further problem is caused by diving at slack water; the direction of the current reverses during slack, so although the weight may be securely up current of the obstruction before slack, after the tide turns the weight is down current of the obstruction and may drag.

At the surface, the direction of the current is indicated by three signs at the buoy: the direction of the line to the weight, a "horseshoe" bow-wave on the front of the buoy and a wake at the back of the buoy.

Sometimes, two buoys are used at the surface. The second buoy can further indicate the strength and the direction of the current or be misleading because it may indicate the direction of the wind. A second buoy can be used to provide additional buoyancy if one buoy is dragged underwater.

Sometimes the line, once at the dive site on the seabed, is tied to the dive site to guard against the weight dragging away from the site. The line itself may be tied to the dive site or a thin "waster" line may attach the strong line to the dive site. If a waster is used, the boat at the surface can be used to break the waster at the end of diving before the shot is lifted. If the main line is attached to the dive site, the divers must untie it before ascending at the end of diving otherwise they lose their shot.

In a current, the buoy may be dragged under the surface by water resistance of the divers holding the line as they ascend and reach shallow water. If this happens divers will not want to descend with the buoy and will prefer to release the shot line and be swept away from the shot. In strong currents divers often decompress on decompression buoys instead of using a shot.

Sometimes, a lifting bag is attached to the weight and used to help raise the weight at the end of the dive.