Sharkfood island, top middle position, sniper can hit back end of your base?

[Necrocat219]

The sniper has a range of 3

On Sharkfood island the base is 3 hexes away, and can be hit

In your example, the base was 4 hexes away from your sniper, so it can't be hit as the sniper doesn't have that long a range. imagine there are 'real' tiles, it's got nothing to do with if it's the edge of the map or not, you just aren't close enough.