Shoot projectiles call onActionProjectile2 when they land/hit someone.
PHP Code:
//#CLIENTSIDE
function onActionProjectile2() {
echo("Projectile landed: " @ params);
}
Before using shoot it helps if you store the player's account or some unique identifier so you can figure out where it came from when the projectile lands in the projectile's parameters. I.e:
setshootparams("missile", player.account);