Spaceships: Missile launchers and their individual mass

[d_ns]

Pardon if this has been covered elsewhere...

Oh, and warning! Math ahead!

So, according to the Spaceships PDF, as missiles increase in diameter by initially 4cm, and eventually 8cm at a time, their mass increases by a factor no higher than 2.0. At the same time, based on the unloaded mass calculations, launchers themselves, increase in mass by a factor no less than 3.0.

Is this as expected? Is the machinery required to deal with launching missiles likely to increase in size more rapidly than the missiles themselves? The numbers begin to get, well, pretty crazy over time:

Missile  Unloaded   Missile   Missile   Magazine  Magazine  Total Ammo  Launcher  Launcher
 Size      Mass    Unit Mass  Multiple  Capacity  Multiple     Mass       Mass    Multiple
-------  --------  ---------  --------  --------  --------  ----------  --------  --------
20cm       1.5        0.20       --         7        --         1.40       0.10      --

24cm       5.0        0.33      1.67       10       1.43        3.33       1.67     16.7

28cm      15.0        0.50      1.5        15       1.50        7.50       7.50      4.5

32cm      50.0        1.00      2.0        20       1.33       20.00      30.00      4.0

40cm     150.0        2.00      2.0        30       1.50       60.00      90.00*     3.0

48cm     500.0        3.00      1.5        50       1.67      150.00     350.00*     3.9
 
56cm    1500.0        4.00      1.33       70       1.40      280.00    1220.00*     3.5

64cm    5000.0        7.50      1.88      100       1.43      750.00    4250.00*     3.5

*  Weapons at this size begin to include workstations; 1 at 40cm, 3 at 48cm, 10 at 56cm and 30 
   at 64cm. Working from somewhere between a Control Room station and a Passenger Seat, we can 
   call this roughly one ton per workstation, reducing the size of the weapon itself by insignificant 
   numbers (from just over 1% to just over 0.7%)

Imagine my surprise; I started this project thinking that smaller missile launchers ought to have larger magazines than the big ones - boy was I wrong!

In point of fact, I begin to think that the magazine size for these launchers needs to be growing at a much higher rate, to keep the launchers themselves (and the attendant hardware, etc) from growing beyond all common sense.

Thoughts?