Spinal mounts in MgT HG

[McPerth]

Regarding computers and oversized ships, I think it would be solved by running several in parallel, though there is no mechanism in the rules for this, or by degrading ship performance.

I calculated that at TL7 you end up with large Intel mainframes taking up a stateroom.

Once again, I see this as cheating the design system.

It's already stated (page 65 of MgT LLB2:HG) that:

Capital ships have multiple distributed computer networks, but always include a central computer core that controls the ship’s
Jump engines

.

So, I understand that the core computer is the coordinating one for all those multiple distributed computers, so, the runing paralel systems you talk about is already accounted for, with the core computer maximum being the highest result achievable at this TL by this paralel network.

 

[rancke]

So, I understand that the core computer is the coordinating one for all those multiple distributed computers, so, the runing paralel systems you talk about is already accounted for, with the core computer maximum being the highest result achievable at this TL by this paralel network.

MT gave ship designers the option of installing multiple computers (IIRC three was actually the minimum).

Incidentally, I vaguely recall a rule in HG about installing backup systems. So why don't ship designers install a backup computer or two to ward off the effects of one critical hit result at least?


Hans

 

[McPerth]

MT gave ship designers the option of installing multiple computers (IIRC three was actually the minimum).

You remember right, three computers (main and 2 back-ups) were the mínimum in MT for spaceships/starships, but never said that they could be used to allow your ship having more CPs than the computer could handle as imput (the way MT had to limit the size by computer class), even in at least one official design (IIRC the X-boat Tender in HT) used this "cheat".

Incidentally, I vaguely recall a rule in HG about installing backup systems. So why don't ship designers install a backup computer or two to ward off the effects of one critical hit result at least?

You can build as many back-ups as you want, AFAIK, but you cannot build more computers to overcome the size limits (again AFAIK). After all, there's no rule that says X computers equal one of higher rate, so there's not even a way to handle it by rules.

After all, only MT (as told above, and again AFAIK, as I know not all versions) gave the limit in other way than just X computer is needed as minimum for Y sized ship (CPs) that could be used to so "cheat" this limit...

 

[Condottiere]

The loophole appears to be that bridge/computer need only control the hull they are integral to, which leaves the gate open for these ships to act as tugs or attach pods to.

However, I do believe that for calculating/controlling the hyperjump process/machinery you need the requisite computer.

 

[McPerth]

However, I do believe that for calculating/controlling the hyperjump process/machinery you need the requisite computer.

Calculate jumps is an entirely diferent thing in MgT HG. Even if you ship is quite small, The computer required to jump is dependent on the computer number (but the rules are not clear about this, as they talk about jump mínimum, but if that is the jump that needs this computer or better, then there's conflict on jump 6).

 

[Dagrill]

I'm afraid you're wrong here...

According to page 66 (at least on MGT LBB:HG, not sure about the page in large book, though I think it will not change) an A rated Meson Spinal is 5000 dtons at TL 11, but at TL +4 (so 15) it's size is reduced by 80%, so being 1000 dtons in size.

PA Spinals are less reduced by TL, so the smallest of them is 3000 dtons (5000 dton at TL 8, -40% at TL +4).

Hi,

You would need power plant 5, 50 staterooms for 100 crew as well and fuel, you might be able to make a very potent monitor, or battle rider though....

I might have a go at such a design.

Regards

David

 

[McPerth]

Hi,

You would need power plant 5, 50 staterooms for 100 crew as well and fuel, you might be able to make a very potent monitor, or battle rider though....

I might have a go at such a design.

Regards

David

Why PP 5?

According the table in page 64 PP 2 is enough for a Spinal...

 

[Dagrill]

anyway, back on topic, i noticed this as i was statting up a 10 Kton, TL 10 "battleship", to see what it would look like. not finished yet, but the results so far are....intresting. max armour of only 10 points, no screens, and that spinal eats up a huge amount of the tonnage. it's inaccurate as well, as the limited fire control software does not make up for the stiff base to-hit values.

On the surface, i'm not wholly conviced that at TL 10, a spinal mount ship would be able to beat a non spinal ship. I've not dug into the maths to check, but massed barrage fire could well do some serious damage, maybe more than a spinal could do.

Might be worthwhile drawing up a TL10, 10 Kton "super destroyer", armed with a metric shedload of missle or torpeado bays, or even railgun bays (12 points per 50 ton bay in a barrage, unaffected by defensive fire? thats going to get painful, quickly), and then throw them agianst each other.......

edit: another thing that effects ship design: since screens are hundreds of years, and 2 Tech levels, in the future, the best protection you can get again radiation is the rad sheild hull upgrade, which is fine.....in just costs a MCr per 4 tons. my 10 Kton ship has a 100 Mcr hull, with 50 Mcr armour....and 2500 Mcr of rad shielding. It's looking at about 25-33% of the total cost of the ship. I wonder if the effects are enough to allow 3 rad sheilded ships to take on 4 non shielded ships.....

Radiation shielding is vital as it protects against Meson hits....
I stick it on all my designs, but I've failed to produce an effective TL10 10kt 'battleship'. The Spinal Rail Gun B is too big to fit, haven't tried an A, but you have to get awfully close too use it...

Bays are probably the way to go (only 2 crew per bay)

Regards

David

 

[Dagrill]

another oddity i have just noticed: their is a disconnect between the starship (ie sub capital) and capital ship computers and their processing power.

A max spec, TL 15 Model 7 starship computer has a rating of 35 and costs 30Mcr, but the captial ship Core/3 is rating 40 at only TL9 and just 12 MCr.

Core 3 does have a minimum ship size of 3 kt, but with the structure per section split you wouldn't build 3kt ships under these rules, good bye Aslan Intruder Transport.

Regards

David

 

[Dagrill]

The railgun must come to short range before being able to hit. I'd better arm the super destroyer with PA turrets. With so many of them with 3D damage each and long range, it has an impressive barrage, and also does radiation damage. Not sure if they are affected by sandcasters in MgT (but the table for sandcasters in barrage fire, in page 74 of MgT LBB2:HG only talks about lasers and missiles, so I guess they're not, as was in CT/MT).

Rail Gun Spinal's have a Medium range (per TCS), I'd like to arm a ship with one, but they just aren't powerful enough compared to the PA spinal...

Regards

David

 

[Dagrill]

Incidentally, I vaguely recall a rule in HG about installing backup systems. So why don't ship designers install a backup computer or two to ward off the effects of one critical hit result at least?
Hans

I think Computers are linked to the Bridge space, but you can install a back up Bridge, or power plant, or any other system. You do need a size (in tons) for computers to install back ups

Regards

David

 

[Condottiere]

Mongoose blueprints show a section cordoned off for the computer, but I expect it's an excuse for a mancave for the Captain to play first person shooter games.

 

[Xerxeskingofking]

well, some intresting and enlightening feedback, i must say. and I'm plesantly suprised that this is stimulating so much conversation (i log back on and find 2 whole pages of posts about my comment. )

Radiation shielding is vital as it protects against Meson hits....
I stick it on all my designs, but I've failed to produce an effective TL10 10kt 'battleship'. The Spinal Rail Gun B is too big to fit, haven't tried an A, but you have to get awfully close too use it...

Bays are probably the way to go (only 2 crew per bay)

I refered to it as a battleship because for a TL 10 polity (say, early Interstellar Wars -era Terrans), it would be the biggest ship that could be built. It might still be a viable cruiser at TL11, but the extra 40,000 tons of space a TL 11 ship can have means it can mount a much more fearsome secondary battery, as the spinals aren't that much bigger, but it has 5 times as many hardpoints to play with.

No wonder the terrans got their arses kicked in the early Interstellar Wars! However, unless i'm misreading the wiki, they seem to have shot though TL10 at record pace . In -2431, they discover the jump drive, so that's late TL9/early TL10. Terran jump 2 (i.e. TL11) ships are mentioned at the start of 2nd IW in -2393, just 38 years later. that seems remarkably fast, even if they were somehow able to aquire Vilani J2 drives.

anyway, your right that missle bays give me a lot of bang for buck, with only 100 hardpoints to play with, it's hard to mount many without eating deep into your point defense turrets.

My design is starting to shape up, and it;s looking like at 10Kt you might be better pushing for very heavy offensive armement (missle bays) with only a very light defensive suite (lasers and sandcasters). i can easily put a lot more missles in the air than i can lasers to stop them, so i might as well go for a minimal point denfence and sandcaster suite and use those hardpoints for bay weaponry instead.

Spinal rail guns? not come across them. TCS, you say? i was under the impression that was a mainly a fluff book. does it have a lot of extra ship options? I've gone with a PA spinal, type A-10, 4000 tons, 220 damage.

Read last sentence, first paragraph page 79 of MgT LBB2;HG:


Ships with armour ratings of 8 or more ignore radiation hits from all but meson weapons.

So no, it's not worth it

*sigh* I thought i'd read these rules, but it appears not......

thankyou for (agian) pointing out something i'd missed. that rule is rather handy. Bit of a change form the core rulebook, I'm suprised its not more marked. thankfully it's eaisy to take out.....



Anyway, like i said, the ships starting to firm up. even with a quite modest number of bays (15 100 ton missle bay-9), i can put 360 or so missles into a single barrage (80% bearing, so 12 bays, 24 missles each) whereas i'd need something like 150 triple laser turrets to match that, more than i can mount, so it seems that point defence, if you will excuse the pun, is pointless. i think i might strip the PD down to just 10 or 15 turrets (for antifighter work) and invest the rest in bays. I got more space left over than i expected anyway, so it's either add more bays and ammo, or start adding in mission creep extras.

 

[mike wightman]

There is no secret to the rapid advance of Terra. The Vilani Imperium had no prime directive and trade was perfectly possible, The Terrans bought their way to TL10.

The next sep is thanks to espionage and reverse engineering.

As to MgT TCS it does have quite a few pages about new ship systems.

 

[McPerth]

well, some intresting and enlightening feedback, i must say. and I'm plesantly suprised that this is stimulating so much conversation (i log back on and find 2 whole pages of posts about my comment. ).

That's why I thought it deserved its own thread, instead of a cross discussion in another one...

I refered to it as a battleship because for a TL 10 polity (say, early Interstellar Wars -era Terrans), it would be the biggest ship that could be built. It might still be a viable cruiser at TL11, but the extra 40,000 tons of space a TL 11 ship can have means it can mount a much more fearsome secondary battery, as the spinals aren't that much bigger, but it has 5 times as many hardpoints to play with.

No wonder the terrans got their arses kicked in the early Interstellar Wars! However, unless i'm misreading the wiki, they seem to have shot though TL10 at record pace . In -2431, they discover the jump drive, so that's late TL9/early TL10. Terran jump 2 (i.e. TL11) ships are mentioned at the start of 2nd IW in -2393, just 38 years later. that seems remarkably fast, even if they were somehow able to aquire Vilani J2 drives..

In fact, at TL 11 your 50000 dton ship has more than just the 40000 extra dton for additional weaponry, as also your PA Spinal is reduced an additional 10% in size (and damage raised by a 5% more...). Also at TL 11 meson guns (both Spinals and Bays) appear, making your ships deadlier than TL 10 ones not only due to size.

anyway, your right that missle bays give me a lot of bang for buck, with only 100 hardpoints to play with, it's hard to mount many without eating deep into your point defense turrets.

My design is starting to shape up, and it;s looking like at 10Kt you might be better pushing for very heavy offensive armement (missle bays) with only a very light defensive suite (lasers and sandcasters). i can easily put a lot more missles in the air than i can lasers to stop them, so i might as well go for a minimal point denfence and sandcaster suite and use those hardpoints for bay weaponry instead.

Spinal rail guns? not come across them. TCS, you say? i was under the impression that was a mainly a fluff book. does it have a lot of extra ship options? I've gone with a PA spinal, type A-10, 4000 tons, 220 damage. .

I disagree about the fact that missiles give you beter bang per buck, at least against PA turrets. Missiles have a 2 dice (assuming you're using nukes, off course) against the 3 for the PB, so having a -1 to the roll against armored ships, and are affected by sand and lasers. This aside, your 360 nuclear missiles barrage would cost you (at Cr 45000 per dozen) Mcr 1.35, while the PAs ammo is free. You'll also need to dedícate 20 dtons per salvo to ammo, while, again, the PAs don't need it. Off course, fewer PAs will fire than missiles, but its effect can be increased (and more so against fighters, if we asume only one gunner per bay or turret, as you cannot hit more fighters than gunners you have...)

*sigh* I thought i'd read these rules, but it appears not......

thankyou for (agian) pointing out something i'd missed. that rule is rather handy. Bit of a change form the core rulebook, I'm suprised its not more marked. thankfully it's eaisy to take out......

Sorry to correct you again about rules, but this changes nothing from the Core Book (aside from the words to explain it): in the Core Book, armor is subtracted from the radiation damage roll, and a 4- means no damage, so armor 8 makes you impervious to nuclear damage except for mesons (as specified in HG).

About using the anti radiation armor against mesons, as mesons don't appear until TL 11, a TL 10 (as you say, ISW) will not fear what does not know to exist and don't see as a threat. Off course, if you must face a TL11+ foe, things change...

 

[Xerxeskingofking]

don't be sorry, I'd rather look stupid now rather than work up a ship thats based on patently false assumptions.

my point about missles is that i can put hundreds of missles in the air via bays, but i can't mount the same number of PA turrets, due to hardpoint limits. i've revised the design a bit more, couldn't get the ammo bunkerage i wanted for 15 100 ton bays, so i downgraded and now have 20 50 ton bays. thats 192 missles a savlo (max bearing= 16), or a 384 point salvo. for 20 PA turrets, its 60 PAs, or only 180 point salvo.

thats what i meant. i can put a lot more potential damage in the air, and i think i can put enough in the air to cause more even after the PD has it's way. On the current draft, I've got 20 triple laser and 20 triple sandcasters. that 96 barrels that can be pointed at a barrage. i've got more than enough to swamp the PD that i can put up. Hell, I can get over the 110% ratio for a 10 Kdt spinal ship with nothing but PD (60 turrets, 48 bearing 144 barrels, which gives us a missles/PD ratio of 1.37 : 1).



Also, can you use PA's in point defense? The rules refer to just lasers in a point defense context. Not saying you can't, just trying to get a clearer idea.

 

[Xerxeskingofking]

right, my TL10, 10,000 ton captial ship, in a somewhat raw form. I'll tidy it up, work out it's crit charts and so on, then write up some fluff and post it over in the Fleet board.

I'm sure thiers at least one error in thier somewhere (based on past experience), so feel free to point it out.


TL 10 battleship.

Size= 10,000 Dtons (CF), standard (100Mcr)
armour Crystalion 10 points (12.5% of hull. 1,250 tons, 50% base cost, 50Mcr),
Hull/Structure points: 142/142 3 sections each with 42/42

M Drive: 6 G (325 tons, 162.5 Mcr)
J drive J1 ( 200 tons 400Mcr)
P plant: TL 10 fusion, P6 (625 tons,1250 Mcr)
Fuel: 1 jump 1 and 4 weeks. (1750 tons)

running total 4150 tons, 1962.5 Mcr

Bridge spaces: 150 tons, 15Mcr
Computer: Core/4, 20 MCr
sensors: 3x Basic Military (6 tons 0.3 Mcr)
Fuel processors: 10 tons (all fuel in 1 week) 0.5 Mcr

running total 4316 tons 1998.3 Mcr.

weapons:
Spinal mount: Particle A-10, 220 damage. 4000 Tons, 2800 Mcr 40 hardpoints)

tons 8,316 tons.4798.3 Mcr
turrets:
20 Triple Beam laser 10, High Yield, max bearing 16 (20 tons) 86 Mcr
20 Triple sandcaster, max bearing 16 (20 Tons) 35 Mcr
ammunition: 60 tons (1,200 barrels, cost 12 Mcr)
running totals 8,416 tons 4931.3 Mcr

Bays (bearing 80%):
20 x small Missle bay-9: max bearing 16 (31 tons each) 620 tons, 360 Mcr.
ammunition: 240 tons ( 2,880 missles, or 12 missles per tube) cost 129.6 Mcr for nuclear missiles
tons 9,276 tons. 5420.9 Mcr
Extras:
4 briefing rooms (32 tons, 2 Mcr)
5 armouries: (10 tons, 2.5 Mcr)
2 Slow Pinnaces in full hangers (104 tons, 20.8 MCr for hanger, 30.09 Mcr for craft)
9318 tons 5476.29

crew totals (normal strength)r:
command: 10
Engineering: 12
gunnery: 120
flight: 4
Ships Troops: 30
Service: 20
total: 196. 103 staterooms, 412tons 51.5 Mcr)


total 9730tons

Cargo: 194 tons.

Totals:
tonnage 10,000 tons
cost: 5,527.5 Mcr

 

[McPerth]

right, my TL10, 10,000 ton captial ship, in a somewhat raw form. I'll tidy it up, work out it's crit charts and so on, then write up some fluff and post it over in the Fleet board.

I'm sure thiers at least one error in thier somewhere (based on past experience), so feel free to point it out...

Personally, I don't see the A rated spinal as too useful, at least when pitched against similar ships, as the Spinal damage is reduced by 30 points per armor point (with a minimum damage of 10% counted as barrage damage), so it would inflict only 22 points against any ship with armor 8+ (that would also be impervious to radiation damage). And to hit it needs a formidable task (so 14+) modified by crew quality and fire control (but to fire it you must burn some initiative to "Line the Spinal Mount"). If we asume a crew quality of 3 and Fire control +3, it needs a 8+ to hit for those 22 points of damage.

Those same 40 hardpoints used on PA turrets (32 bearing) would give you a barrage of 96-PA-long-3, that, against an armor 10 ship (and assuming the same +3 crew quality and +3 FC) would fire with a -1 DM (-10 per armor, +3 per dice/weapon, +3 quality, +3 FC), so, on this same 8 roll, damage would be 100%, so 96 points (over four times the spinal), while on a boxes roll would yeld up to 200%, so 192 damage points, and will only fully miss on a 3- (so, in any roll, it will inflict more damage than your PA Spinal). All this aside, this change would free quite a space and be quite cheaper....

Also, I see your PP oversized by its needs (again increasing tonnage and cost), as a PP 2 would be enough for the JD, MD, Spinal and up to 2 eneregy weapons bays (your design has none, so that's more than enough).

my point about missles is that i can put hundreds of missles in the air via bays, but i can't mount the same number of PA turrets, due to hardpoint limits. i've revised the design a bit more, couldn't get the ammo bunkerage i wanted for 15 100 ton bays, so i downgraded and now have 20 50 ton bays. thats 192 missles a savlo (max bearing= 16), or a 384 point salvo. for 20 PA turrets, its 60 PAs, or only 180 point salvo.

Let's see salvo results:

to make numbers easy, let's imagine your 20 missile bays against 20 PA turrets (as both use a hardpoint each, though I guess, due to size, a ship could bear more PA turrets than bays). In both cases 16 bearing:

Missiles barrage: 384 - nuclear missile - long - 2
PA barrage: 48 - PA - long - 3

Against an armor 10 ship, in all cases crew quality 3 and FC +3:

Missiles modifier: -10 armor, +2 dice/weapon, +3 crew, +3 FC, - (1d6-1¹+1) sandcasters, -(1d6-2¹+1) for lasers= -(2 + (2d6-1)), so, -(2d6+1). So, assuming average dice, no damage (as the dice for PD will offset barrage roll and still leave a -1 result).

I asume PD is under 90% of missiles in both cases​

PA modifiers: -10 armor, +3 dice/weapon, +3 crew, +3 FC= -1. So, only on a 3- they do no damage.

Of course, a lucky missile barrage can be devastating (both PD rolls being 1, so a total of -3 and boxes on the barrage roll would inflict 150%, so 576 damage points, But you need a barrage roll 4 over the PD roll to inflict any damage (I leave the numbers to anyone else). And again, against fighters things go even worse.

EDIT:

for 20 PA turrets, its 60 PAs, or only 180 point salvo.

See page 47 of MgT LBB2:HG (under Weapons, Changes to Core Book Rules):

Only one particle beam can be fitted to a turret, but this must be a triple turret

And MongooseMatt clarification in another thread:

Only one PB to a triple turret...

So, in this point, the 20 PA turrets would be 20 PAs, so only 60 point salvo (this time in your favor, but even then, again IMHO, I guess they are more cost effective than missiles, as told above)

 

[Xerxeskingofking]

Personally, I don't see the A rated spinal as too useful, at least when pitched against similar ships, as the Spinal damage is reduced by 30 points per armor point (with a minimum damage of 10% counted as barrage damage), so it would inflict only 22 points against any ship with armor 8+ (that would also be impervious to radiation damage). And to hit it needs a formidable task (so 14+) modified by crew quality and fire control (but to fire it you must burn some initiative to "Line the Spinal Mount"). If we asume a crew quality of 3 and Fire control +3, it needs a 8+ to hit for those 22 points of damage.

erm, isn't fire control/3 a TL11 program? obviously not a problem in the 3I but might be in a pure TL 10 setting

anyway, it still answers the question of wether a spinal is a viable weapon at this level, since as you point out it's almost ineffective vs properly armoured warships.

Those same 40 hardpoints used on PA turrets (32 bearing) would give you a barrage of 96-PA-long-3, that, against an armor 10 ship (and assuming the same +3 crew quality and +3 FC) would fire with a -1 DM (-10 per armor, +3 per dice/weapon, +3 quality, +3 FC), so, on this same 8 roll, damage would be 100%, so 96 points (over four times the spinal), while on a boxes roll would yeld up to 200%, so 192 damage points, and will only fully miss on a 3- (so, in any roll, it will inflict more damage tan your PA Spinal). All this aside, this change would free quite a space and be quite cheaper....

so, agian, harking back to our orignal discussion, you think that the "super destroyer" would work better at TL10? which does kind of raise the question of who would sink the RnD time into improving spinals when they are a sub-optimal option.......

noteably, i we go with a non spinal mount design, we free up a lot of space for multi mission extras. I'm sure i could slap a company of marines and enough shuttles to land them in that space....

Also, I see your PP oversized by its needs (again increasing tonnage and cost), as a PP 2 would be enough for the JD, MD, Spinal and up to 2 eneregy weapons bays (your design has none, so that's more than enough).

I went with the bigger P plant becuase i felt 6g would be at least somewhat useful. for running away, it nothing else. the first draft i had only 3g, but i felt that the extra speed was a better use of a few hundred tons than the extra missle bays would have been.

Let's see salvo results:

to make numbers easy, let's imagine your 20 missile bays against 20 PA turrets (as both use a hardpoint each, though I guess, due to size, a ship could bear more PA turrets than bays). In both cases 16 bearing:

Missiles barrage: 384 - nuclear missile - long - 2
PA barrage: 48 - PA - long - 3

Against an armor 10 ship, in all cases crew quality 3 and FC +3:

Missiles modifier: -10 armor, +2 dice/weapon, +3 crew, +3 FC, - (1d6-1¹+1) sandcasters, -(1d6-2¹+1) for lasers= -(2 + (2d6-1)), so, -(2d6+1). So, assuming average dice, no damage (as the dice for PD will offset barrage roll and still leave a -1 result).

I asume PD is under 90% of missiles in both cases​

PA modifiers: -10 armor, +3 dice/weapon, +3 crew, +3 FC= -1. So, only on a 3- they do no damage.

Of course, a lucky missile barrage can be devastating (both PD rolls being 1, so a total of -3 and boxes on the barrage roll would inflict 150%, so 576 damage points, But you need a barrage roll 4 over the PD roll to inflict any damage (I leave the numbers to anyone else). And again, against fighters things go even worse.

EDIT:

See page 47 of MgT LBB2:HG (under Weapons, Changes to Core Book Rules):



And MongooseMatt clarification in another thread:



So, in this point, the 20 PA turrest would be 20 PAs, so only 60 point salvo (this time in your favor, but even then, again IMHO, I guess they are more cost effective than missiles, as told above)

I must point out that the pimary limiting factor i faced was not tonnage but hardpoints, and i could quite happily replaced every missle bay with a particlebarbette and come out about 500 tons ahead. Or just replaced the missle bays with particle bays, which would have worked as well.

 

[McPerth]

erm, isn't fire control/3 a TL11 program? obviously not a problem in the 3I but might be in a pure TL 10 setting

You're right, I didn't realize the TL minimums for programs, as Iguess we're talking about a pure TL 10 setting (e.g. ISW). See that this makes more against missiles overcoming the PDs in the end of my post...

so, agian, harking back to our orignal discussion, you think that the "super destroyer" would work better at TL10? which does kind of raise the question of who would sink the RnD time into improving spinals when they are a sub-optimal option.......

noteably, i we go with a non spinal mount design, we free up a lot of space for multi mission extras. I'm sure i could slap a company of marines and enough shuttles to land them in that space....

Agreed

I went with the bigger P plant becuase i felt 6g would be at least somewhat useful. for running away, it nothing else. the first draft i had only 3g, but i felt that the extra speed was a better use of a few hundred tons than the extra missle bays would have been.

You're right. I again overlooked the Maneuver drive 6 (it seems now is my turn to overlook things )

I must point out that the pimary limiting factor i faced was not tonnage but hardpoints, and i could quite happily replaced every missle bay with a particlebarbette and come out about 500 tons ahead. Or just replaced the missle bays with particle bays, which would have worked as well.

But tonnage will also be a factor, if not the main one, as you need one ton for a turret but 50-100 for a bay (and, in both cases, to this you must add the crew accomodations, ammo storage if they use it, etc...)