Stroud & District Clay Club
Down-the-Line - usually called: DTL - is the name given to a Clay target discipline, popular in the UK as a form of Trap shooting. There is a family of Trap Disciplines with increasing difficulty, culminating in Olympic trap. DTL is essentially a domestic discipline, which is also shot in several other countries, whereas many of the other Trap diciplines are International. One thing for sure: it isn't easy to consistently break them all!
Wikipedia has a useful article on DTL.
The illustration shows that a Traphouse throws clay targets through an arc of 64° such that they will land some 50 yards in front of the traphouse, which itself, is some 16 yards in front of the shooters. The Trap randomly oscillates across this arc and releases a Clay target when a Shooter calls "Pull".
DTL is shot in a 'round' of DTL; there are 25 targets in total and competitions are often shot as four rounds, ie 100 targets.
Shooters, in a squad of up to five, take turns to shoot from each of five Stands (1 - 5). Each Shooter takes it in turn to shoot at one target: ie the Shooter at Stand 1, followed by the Shooter at Stand 2... etc. When each Shooter has shot once, the Shooter at Stand 1 shoots at another target, followed by Shooter 2... When each Shooter has shot at five targets, the squad moves to the next stand, ie the Shooter at Stand 1, moves to Stand 2... and the Shooter at Stand 5, moves to Stand 1. This process is repeated, so that each Shooter has shot five targets, from each Stand.
When the squad is ready, each shooter is standing on their appropriate Stand and ready to shoot, they load with two cartridges for a single target. When ready, a Shooter shouts 'Pull' and a target is released. Shooters can use one, or both, cartridges on the same target as required.
Cartridges have a maximum load of 28g, with 24g being not uncommon; a shot-size of No 7½ is usual, but not mandatory. When each shooter is standing on their appropriate stand and ready to shoot, they load with two cartridges for a Single target. When ready, shooters shout 'Pull' and a clay target is released.
Scoring is 3 points for a target broken using the first barrel (first cartridge) and 2 points for a target broken by the second barrel (second cartridge). With 25 targets to shoot at for each shooter, there are up to 25 * 3 = 75 points per round. Scoring is thus a combination of clays his and points scored, so 25/75 means that 25 targes were broken and 75 points scored.
DTL is a high scoring discipline as, generally speaking, the targets are not difficult to hit; the problem is hitting them all, preferably using only the first barrel!