Most of the flare types weapons you've seen deal area damage, this is the complete opposite of them, where the flare ball stops is where the damage will take place specifically. 15 "pins" will rain down from the sky in a almost straight line. Each pin deals 4 damage and does not break the terrain. Be careful of the wind because it can nudge them away from where they should land.
The final upgrade of this weapon series, it packs a mighty punch firing a large amount of both pins and needles. They are identical in stats however, so the "pins and needles" skin is entirely vanity.
If you look carefully, you can see that the attack actually drops in 3 separate lines.
This weapon penetrates shields.
The projectiles spawned by this weapon do not explode when they hit tanks directly, they only explode on contact with the ground. If you try to hit a player that is on a wall with this weapon, the projectiles could go through their tank and hit the ground further beneath them, resulting in 0 damage.
It appears that when pinpoint's projectile hits a tank, it disappears and creates an explosion on the ground directly below the projectile, whether or not that part of the ground is touching the tank it hits.