Update! There is now a bp for a requester chest which requests all the items required for building the base (except for blue belts and undergrounds)
This is a car (tank works too but no big benefit) based artillery base, inspired by the 'hit and run artillery video'. The idea is you can drive to anywhere in your world and have a secure base just like that (for artillery). It can also be easily removed to move it somewhere else. It is recommended to have at 4-8 personal roboport mk2s for the building process, 1 works fine but it is pretty slow.
This is a relatively late game build requiring uranium ammo, blue belts (could use red/yellow but not recommended, this goes for belts and ammo) and some fringe items like light oil barrels and two efficiency two modules
Car setup: 2-3 rows of light oil barrels, 1-2 rows of uranium ammo, the rest filled with artillery ammo (it is also recommended to have a lot of your inventory filled with artillery shells as the cannons go through them fast)
Make sure you have the materials needed! (repair packs are also good)
Setup:
Step one: drive to the desired location and pull out the blueprint, line up the car with the 2x3 gap in the middle (it is actually 2x4 but that is for tank compatibility)
Step two: place it and wait for your robots to do the work (note: it requires solar panels only for inserters + assembling machine and it will look like theres not enough power but that is only because all inserters are running at once to fill the gun turrets)
Step three: once you have all the turrets filled, and you are happy about accumulator charge, hit 'r' twice on both inserters connecting the vehicle to the artillery
Step four: let it rip! (there is a gate for getting in and out so if you need more artillery ammo you can do supply runs in a different car if its not too far)
Step five: flip the inserters feeding the artillery again (if theres any left), then flip the inserter going into the barrels and the inserter going from the car to the assembling machine (note: it is a filter inserter feeding the assembly machine as i found it was very annoying when it picked up uranium ammo, and it has a very low power hit). You then change the inserter recipe to creating light oil barrels, and flip the assembling machine as it resets the pipe input/output. when this is done you should be ready to pack up by just marking it all for deconstruction!
I hope this works and i would really appreciate any feedback