Gun details
Click on the gun selection area to bring up the firearms menu.
You can create records for multiple guns and the values on the "Basics" screen are fairly self-explanatory.
It is recommended that you get someone else to measure the distance from your eye to the bead when you are in the shooting stance.
Chokes
You can have the same or different chokes in each barrel.
You can select standard chokes, edit standard chokes or create custom chokes.
A choke is defined by the spread it generates at two different distances - this represents the way the shot pattern expands over distance..
Cartridges
This screen allows you to select and edit the cartridges you are using - usually the same in both barrels but you can make them different if you wish.
POI
POI (Point Of Impact) defines where, at a specific distance, the centre of the shot pattern goes in relation to where the gun is pointing.
Sporting and skeet guns usually put 50% of the pellets above and below the point of aim. Trap guns may put 70%, or even more, of the pellets above the point of aim - to hit a rising target.
The POI screen allow you to define your gun's POI.
To establish your gun's POI in the real world you will need to visit a shooting ground with a real pattern board.
Pattern board
Selecting the "Pattern" button brings up the pattern board.
The pattern board displays the spread of shot at a specific distance given the chokes you have in each barrel and the POI you have defined for your gun..
Click on "Perfect shot" to show the pattern generated on the assumption that the gun was "aimed" at the centre of the pattern board.
Change the "Range" value then use "Perfect shot" to show the pattern at different distances.
The example below shows the pattern board used with POI defined as 75%
