Trap, DTL (Down The Line), ABT (Automatic Ball Trap) are all similar versions of the same shotgun sport.
Five shooters stand in a line facing a trap-house sunk into the ground 16 yards in front of them, centered on the middle shooter. The trap will release one clay target sending it directly away from the shooters within a fixed arc. The target's elevation is controlled according to the rules of the game being shot
Doubles, Double-Trap and Double-Rise are variations on the above games, but release two targets at a time instead of one.
All games basically use the same trap-field layout, the differences are target trajectories, speed of target and scoring.
Let's take a look at the field to the right.
This is a typical ATA (American Trap Association) TRAP layout.
There are normally five shooters standing in an arc facing the trap-house (in the above photo, shooter 2 is missing so you can see the trap-house). The shooters take turn in shooting at the target released from the house. You can see the target (red line) leaving the house. (The target does not always take the same flight path - with TRAP and DTL the target has a fixed vertical height but has a random Left / Right trajectory over a 44 degree horizontal arc. With ABT the target path is random in both horizontal and vertical planes.)
Each shooter will shoot 5 targets from their current position, then all shooters will rotate positions to the right, (i.e. 1 to 2, 2 to 3, etc then 5 to 1).
The shooters will take turns at targets (1,2,3,4,5 - 1,2,3,4,5 - 1,2,3,4,5 - 1,2,3,4,5 - 1,2,3,4,5) Scoring is kept by the referee sitting behind the shooter's line. After all shooters have shot 5 targets at each position they will have shot 25 targets - the game is over.
To add difficulty to the game, shooters are handicapped upon their shooting skills. In the photo above you can see paths (like spokes) radiating back from the forward shooting positions. The forward position is called the 16 yard line. Going backwards, the spokes are divided into one yard squares leading back to the last position - the 27 yard line. Only very experienced shooters obtain a perfect score shooting from the 27 yard line.
(Note: When shooters are "squadded", they only mix similar handicap shooters together - otherwise it would be too dangerous to have say, a shooter at the 16 yard line and another at the 27 yard line with risk of shooting the forward shooter.)
