I know this is about “early” when you are ammo constrained.
But my full” production is to setup static artillery turrets in my outposts (I generally play death worlds with expansion on) so they get used plenty.
I have a fairly complex outpost resuppply setup, but for the military portion I send out two trains:
- 2-4 with “standard” ammo wagons
- 2-4 with artillery wagons
I unload into the station from the artillery wagons instead of standard wagons...each one carries 100 shells instead of 40. It also, of course, fires if anything is in range while the shells are unloading up to stock levels. (Though with the static cannons on the perimeter my reload train usually doesn’t have much in firing range...so it mostly just pauses long enough to unload shells.)
At first, when ammo is limited, I generally just build a smaller train, and add additional wagons as I ramp up. In this case you can pretty easily run the train straight to your forward staging area, drop a defensive blueprint down, and fire away.
I just let the automated range do the work and brace for impact. But I’m guessing most people probably manually target too. (As you mention, manual targeting is more likely to hit multiple targets with a single shell.)
And to be a bit more specific on what I consider fun...I don’t run with laser turrets much. I prefer physical and chemical ammo. My perimeter, even for outposts, consists of belt-fed gun turrets, flamethrower turrets, and artillery turrets.
I have a standard set of blueprints to drop all of that into an outpost, along with a resupply station visited by various trains.
When I’m advancing my front, I have an offensive fortification blueprint. My assault train trades the front wagon for a standard wagon. (It’s a 2-4, two locos, same direction, one regular wagon, three artillery wagons.). The standard wagon contains gun turrets, walls, gates, ammo, and a couple other things.
When I stop, I drop the blueprint which places turrets, walls, and gates to enclose the train. It also sets up a quick ammo belt to feed the turrets from the ammo in the lead wagon. While my bots are building all of that, the artillery wagons have trained and started firing. By the time the biter waves hit, the turrets are full and tearing through bugs.
I used to set up flamethrower turrets with the blueprint too, but tearing it down was more time consuming than I liked. It takes a bit of time to reverse pumps and re-barrel the oil to load it back on the train. And nothing survives a solid row of turrets large enough to enclose a 2-4 train anyway.
In the “early” game, you may not have advanced enough bots to quickly build out this more complex defense around the train before it starts firing. So it might be worthwhile to just use laser turrets for pushing forward.
I go heavy military and push to bots early, partially because I know I need those techs to support this play style.
I’m currently playing around with adding segmented roboports to my train blueprints so that I can remotely push into biter territory. It’s tricky, but it’s going to be awesome if I can pull it off.
