So yes, I know that's one cause of inaccuracy. But only one. If it was the major one, then I'd expect that it would affect all shells in a salvo equally, and that the primary cause of misses would be tight patterns landing off-target. This is not really the case. Pattern size was often greater than Mean Point of Impact error. Yes, I'd expect a railgun to be better at consistency than a WWII-era 16" gun. If nothing else, you have a lot lower variation in muzzle velocity. But not enough to make unguided KE rounds work at >10 km.
My point here is that outside influence and moving target is the
ONLY cause of inaccuracy that can't ( and will in an Auorora 4x tech level gun ) be engineered away thanks to smaller tolerances and near molecular level perfect gun assembly.
You're moving the goalposts. This particular discussion started with someone bringing up the Navy's railgun program. Orbital fire support with that kind of velocity of weapons is a very different thing, and a somewhat better case for unguided projectiles.
I'm not moving goalposts. You need to take a step back and realize that your trying to have a discussion about the Navy's railgun program on a forum about a Sci-Fi game. The ultimate purpose of any discussion in this thread as far as I am concerned is to promote a better and more realistic game, not to debate the viability of the Navy's railgun program. If you want to argue about the Navy's railguns I'm sure there are plenty of other forums better suited to that purpose!
That aside, let's assume you're right. Typical battleship pattern size for a 3-gun salvo was about 1% of range. We'll take 10% of that. At 36 km (outer limits of battleship range) you're still missing by an average of 18m (1% is diameter, not radius). An M1 tank has a hull that's 8m long and 3.66 m wide. It covers about 3% of the area we expect our projectile to land in. I'll take my guided projectiles, thank you very much.
Now let's run those math again with Aurora 4x railgun speeds of say 50000000m/s instead of 500m/s as well as orbital range (x10). This mean it's not 10 times accurate, it's 10000 times more accurate. Your average miss turns from 18m to 18cm.
That's not a "somewhat better case"... That's a totally different case.
Something else to consider is that the destructiveness of KE shells scale with speed as well, and not linear but exponential (Ek = ½mv^2). A shell going 100000 times faster contains 100000^2 as much kinetic energy. A 1kg shell travelling at 50000km/s contains about 10 million times as much kinetic energy as a 1000 kg Battleship shell at 500m/s, and about 1 million times as much total energy including HE ( considering about 10% of the energy in a Battleship shell for firesupport would be Kinetic and 90% HE ).
I'm not 100% sure exactly what would happen when shells impact the ground at those kind of speeds, and it's possible the atmosphere would slow them down considerably too, but considering the numbers involved I wouldn't feel safe even 18m away regardless of if I was in a tank or not...
A third consideration ( which Aurora models pretty well already on the scale of space combat at least ) is the cost of the shells vs guided missiles. KE shells are basically free while missiles will cost about 20% as much as the tank it's destroying cost. Using current costs it's $1.87M for a tomahawk vs $8.92M for a M1 tank or 21%. And that's assuming no missiles get intercepted on the way.
Can you please stop assuming things about what I think?
I am not assuming what you (person) think, but what you ( general audience reading ) normally would think.
You are all welcome to join us in discussions improving the game.