Factorio Forums

Is it by design that after pressing space it fires only at the cursor (if it is on a valid target) and does not auto-select targets? To me it seems like a bug but I don't want to flood the bug report forum if it is supposed to work this way.

It is not a bug. You always fire to the direction where your cursor is.

It's hard to tell - all machine gun type weapons fire at enemy near cursor with space and at any entity with c. They don't really fire into space like shotguns do.
Unless something changed in last few versions.

depends what you mean... my default enemies are targeted when you mouse near them, you'll see a little green or red reticle below the target if you're close enough - with red meaning out of range of selected weapon, and green being within range.

If you're not getting seeing this targetting behaviour while your gun is selected (and has ammo) then that would probably be a bug - though you always need to have a target in some way before firing... it's also possible that you're not keeping in mind that the tank machine gun is a fixed mount gun, it points where the turret points, so unlike the player who can pivot their feet and immediately shoot behind them, the tank turret has to rotate... it's part of being a tank =p