[FT] Tech level variation idea (maths!)

IIRC there was a discussion on this list a while ago about representing
variations in tech level by varying the amount if effective space available on
starship designs.

I've been giving this a bit of thought, and have devised the following:

Tech level variation for ship systems.

Essentially, lower tech (than the norm) versions of equipment tend to occupy
more MASS, but COST less, while for higher tech versions, the converse is
true.

The actual change in MASS and COST can be calculated, given that 1 MASS of
empty ship hull costs 1 point.

So if a piece of equipment is enlarged by 1 MASS, it is equivalent to
installing it in a smaller ship, not one exactly 1 MASS smaller, as the change
in the MASS of systems like the Drives and FTL must be considered. So consider
the 'equivalent' ship as being 1.2 MASS smaller (the value chosen assumes a
low amount of Drives plus an FTL, estimating
_not_ in favour of the ship builder). So the system increases in MASS by
1, and reduced in COST by 1.2.

With a bit of mathematics, these figures can be changed to determine the
change in MASS for reducing the COST by 1 per MASS.

New MASS = old MASS x [1 + C/(C-1+1.2)]
where C = COST per unit MASS

If an item is reduced in MASS, the equation becomes:

New MASS = old MASS x [1 - C/(C+1+1.4)]

Anyway, enough math, I decided to design some 'primitive' (compared to the KV)
kinetic energy weapons:

I used the formula above, then adjusted the results to give a nice
progression :-).

Railguns
These use electromagnetism to propel hyper-velocity penetrators,
similar to Kra'Vak K-guns, but somewhat more bulky.

Class of Railgun MASS COST
Class 1 (3-arc)           2       6
Class 1 (6-arc)           3       9
Class 2 (1-arc)           4      12
Class 2 (2-arc)           5      15
Class 3 (1-arc)           6      18
Class 4 (1-arc)          10      30
Class 5 (1-arc)          14      42
Class 6 (1-arc)          18      54

Functions exactly as a K-Gun of equivalent class.

On SSDs, I suggest we just use K-Gun symbols, or the Railgun symbols
Paul Radford used on his UNSC SSDs.

Class 1 railguns (RG-1s) can function as a point defence, like K-1s,
note that 3-arc RG-1s can only attack fighters/missiles in their arc of
fire.

It might be an idea to reduce the range as well, in which case the MASS would
be reduced.

Similarly, an even more primitive system, the Chemically Propelled
Projectile Gun, could be designed :-)

Hope this is of use for someone,

Any comments or suggestions?