Specialist Arms Forum

Battlefleet Gothic => [BFG] Experimental Rules Feedback => Topic started by: Islacrusez on August 19, 2013, 12:48:51 PM

Title: QF guns for smaller ships
Post by: Islacrusez on August 19, 2013, 12:48:51 PM

Strangely, this is a rule inspired through designing weapons turrets. How that happened I don't know, but here it is:

Quick-fire weapons for smaller ships like transports, possibly even small escorts. QF weapons would be short-range weapons that spit out several shells in short succession. The effect of this would be allowing the damage dice to be rerolled a few times. Since the fire-rate would result in a higher likelyhood of hits, but not guaranteeing penetrations, the rerolls would only apply for rolls below a certain number (for example 3 and below), and any above (penetration or not) would count as hits for the purposes of maximum damage output.

Still not sure on the exact balance and whether to go from hits or from rolls...

Basically a small weapon, such as transport dorsals and similar, could gain the special rule QF. Any weapons above 15cm range would increase their power by 1 (or double?) and decrease their range to 15. Each point of strength coming to bear against a target would have 1d6 rolled for it. Any results below 3 (inclusive or exclusive?) would be rolled again, while the rest of the results are kept. Any results from these below 3 (inc/exc) would be rolled again, while the rest of the results are kept. The final result is compared against armour and resolved (though this can be done on the fly, as long as one keeps track of dice and rolls).


It worked better in my head, so if anyone has any better ideas to approach the same topic, would love to hear them!

Title: Re: QF guns for smaller ships
Post by: Islacrusez on August 20, 2013, 12:10:50 PM

I don't like the way that turned out, since it actually just increases the damage output.


Instead:

Any 30cm dorsal battery of strength 1 may be converted to a short-ranged battery of strength 2 and range 15cm.
Any 15cm battery may be converted to QF guns, doubling the strength and reducing armour penetration by 1 (treat enemy armour value as armour+1). For armour 6, the weapon will only cause 1 damage for every 2 hits at 6.

QF guns get a left column shift for firing at ordnance.

Title: Re: QF guns for smaller ships
Post by: horizon on August 20, 2013, 01:05:50 PM

Which type of vessels do you have in mind when you say small escorts?

Title: Re: QF guns for smaller ships
Post by: Islacrusez on August 20, 2013, 02:25:16 PM

I was thinking something like the iconoclast, cobra, that sorta thing. Generally in the destroyer class rather than frigates. However, anything that has a strength 1 30cm dorsal battery could be eligible.

Should also add that the increased firepower from the QF batteries could not be split.

Title: Re: QF guns for smaller ships
Post by: horizon on August 20, 2013, 02:30:27 PM

Good, less imagine. Six Iconoclasts for 180pts.

Quote

Any 30cm dorsal battery of strength 1 may be converted to a short-ranged battery of strength 2 and range 15cm.

That is 6x3 = 18 weapon batteries @ 30cm
I make then QF and it turns into 36 weapon batteries @ 15cm.
That is better then any Battleship out there.

36 batteries on a 30cm fast moving / manoeuvrable vessel. I'll take it!
On All Ahead Full they retain their 18 batteries again. Which is awesomely good after an AAF order.

I think the rule needs some tweaking. Agreed?

Title: Re: QF guns for smaller ships
Post by: Islacrusez on August 20, 2013, 02:38:34 PM

Have you accounted for the armour shift? The reduction in range also hampers their strike distance, bringing it to 45 rather than a terrifying 60.

Title: Re: QF guns for smaller ships
Post by: Cneo on August 20, 2013, 04:16:12 PM

I think it's a bit overpowered, too.

I'd prefer your first idea for the weapon. What about repeating hits like an eldar pulsar?

When the batteries fire from 15cm or less each hit grants you another roll until you fail or score 3 hits. You also won't move a column to the left due to the high rate of fire.

;)

Title: Re: QF guns for smaller ships
Post by: Islacrusez on August 20, 2013, 04:41:59 PM

Quote from: horizon on August 20, 2013, 02:30:27 PM

Good, less imagine. Six Iconoclasts for 180pts.

Quote

Any 30cm dorsal battery of strength 1 may be converted to a short-ranged battery of strength 2 and range 15cm.

That is 6x3 = 18 weapon batteries @ 30cm
I make then QF and it turns into 36 weapon batteries @ 15cm.
That is better then any Battleship out there.

36 batteries on a 30cm fast moving / manoeuvrable vessel. I'll take it!
On All Ahead Full they retain their 18 batteries again. Which is awesomely good after an AAF order.

I think the rule needs some tweaking. Agreed?

I'll expand to account for the armour tweak.

36 batteries, firing at a capital ship, closing, within 12.5 : 32 dice.
Prow armour is 6+, and armour shift means it bounces half the shots that hit. Thus 32/12 = 2.6 hits

Comparing, the same squadron without the modification, 18 batteries, closing and within 12.5 : 16 dice
Prow armour is 6+, so 16/6 = 2.6 hits


Moving away these numbers come to:

25 dice, against 6+ armour = 4.1 hits
and
13 dice, against 5+ armour = 4.3 hits


Abeam, these numbers come to:

18 dice, against 6+ armour = 3 hits
and
9 dice, against 5+ armour = 3 hits


So far the QF guns are losing out. I'm hoping that against escorts it'll balance out a bit better, and failing that it'll just be a really good anti-ordnance tool. Will work out the rest of the numbers later, unless someone else wants to.

Title: Re: QF guns for smaller ships
Post by: Islacrusez on August 22, 2013, 01:15:12 AM

Ok, so the easiest way is just to give the column values for the two scenarios.

I'm assuming horizon's scenario of a squadron of 6 iconoclasts. One value will be for the unmodified iconoclasts' average damage, and one for the average damage of the QF iconoclasts.

The rules for QF weapons are as follows:
A "small" dorsal weapon may be converted to QF, reducing range to 15cm, doubling its strength.
A QF weapon treats the target's armour as armour+1.
In cases where this would make the value 7, the weapon does 1 damage for every two 6s rolled.
QF weapons do not suffer an armour modifier against ordnance, and automatically gain a left column shift (in addition to the range modifier if applicable)

For the time being, Lock-on may not be used with QF weapons as it has no useful effect (trade fire rate to fire accurately, still has low penetration, pass). The sheer amount of dice-rolling would be ridiculous, too!

So I've just re-read my tables and realised that the threshold for column shift is 15, where am I getting 12.5 from? I'll just leave my post as is for now, for my own sanity

Ok, so:
R = dice rolled
D = average damage dealt
a = Armour value for the given damage result

Column	Standard	QF
1	R 16, D 2.6 (a6), D 5.3 (a5), D 8.0 (a4)	R 32, D 2.6 (a6+1), D 5.3 (a5+1), D 10.7 (a4+1)
2	R 13, D 2.2 (a6), D 4.3 (a5), D 6.5 (a4)	R 25, D 2.1 (a6+1), D 4.2 (a5+1), D  8.3 (a4+1)
3	R  9, D 1.5 (a6), D 3.0 (a5), D 4.5 (a4)	R 18, D 1.5 (a6+1), D 3.0 (a5+1), D  6.0 (a4+1)
4	R  6, D 1.0 (a6), D 2.0 (a5), D 3.0 (a4)	R  9, D 0.8 (a6+1), D 1.5 (a5+1), D  3.0 (a4+1)
5	R  4, D 0.7 (a6), D 1.4 (a5), D 2.0 (a4)	R  7, D 0.6 (a6+1), D 1.2 (a5+1), D  2.3 (a4+1)

For a reminder of what's in each column:

Column 1: Defences, Closing Capital within 12.5
Column 2: Closing Capital, Moving Away Capital within 12.5, Closing Escort within 12.5
Column 3: Closing Escort, Moving Away Capital, Abeam Capital within 12.5, Moving Away Escort within 12.5, QF Ordnance within 12.5 (a5+1)
Column 4: Abeam Capital, Moving Away Escort, Abeam Escort within 12.5, Ordnance within 12.5 (6), QF Ordnance (a5+1)
Column 5: Abeam Escort, Ordnance (6)

(Not listed are things that have a right-shift on the table)



Ok, so what does this tell us? Well, first we need to remember that average values aren't everything. While you get a bell curve that means you're far more likely to get the average values on the QF guns, making them more reliable, the chance of exceptional results are much lower but the results are far more significant.

On average, the QF guns are better against: small escorts, and transports (armour 4), almost always better against ordnance. QF guns are not good against armoured targets, performing on par or worse than their ordinary counterparts. Space Marines are pretty well-off against QF fire.

Now, if these results hold, I would consider making a modification that means that the armour penalty is not applied to escort class vessels, which would bring the weapon more in line with its aim - it's an ordnance and escort killer. Or should be. As it stands, it's only useful against Iconoclasts, Transports, and exceptionally useful against Ordnance.


Of course, all that is assuming that these results are valid for all instances of this modification, such as smaller numbers of ships, or smaller numbers of guns per ship.

Title: Re: QF guns for smaller ships
Post by: Islacrusez on August 22, 2013, 12:22:01 PM

Quote from: Islacrusez on August 22, 2013, 01:15:12 AM

Now, if these results hold, I would consider making a modification that means that the armour penalty is not applied to escort class vessels, which would bring the weapon more in line with its aim - it's an ordnance and escort killer.

If I did this though, I'd probably make the weapons ineffective against 6+1 armour, as otherwise the weapon would be overpowered, due to being super effective against a4 and a5 escorts.

Title: Re: QF guns for smaller ships
Post by: Islacrusez on August 23, 2013, 09:40:26 PM

So if here's the above table for comparison,

Column	Standard	QF
1	R 16, D 2.6 (a6), D 5.3 (a5), D 8.0 (a4)	R 32, D 2.6 (a6+1), D 5.3 (a5+1), D 10.7 (a4+1)
2	R 13, D 2.2 (a6), D 4.3 (a5), D 6.5 (a4)	R 25, D 2.1 (a6+1), D 4.2 (a5+1), D  8.3 (a4+1)
3	R  9, D 1.5 (a6), D 3.0 (a5), D 4.5 (a4)	R 18, D 1.5 (a6+1), D 3.0 (a5+1), D  6.0 (a4+1)
4	R  6, D 1.0 (a6), D 2.0 (a5), D 3.0 (a4)	R  9, D 0.8 (a6+1), D 1.5 (a5+1), D  3.0 (a4+1)
5	R  4, D 0.7 (a6), D 1.4 (a5), D 2.0 (a4)	R  7, D 0.6 (a6+1), D 1.2 (a5+1), D  2.3 (a4+1)

And here's the amended table if a6+1 bounces, and escorts don't get their +1:

Column	QF
	Capital Ships	Escorts, Trasports
1	R 32, D 0.0 (a6+1), D 5.3 (a5+1),	D 10.7 (a5), D 16.0 (a4)
2	R 25, D 0.0 (a6+1), D 4.2 (a5+1),	D  8.3 (a5), D 12.5 (a4)
3	R 18, D 0.0 (a6+1), D 3.0 (a5+1),	D  6.0 (a5), D  9.0 (a4)
4	R  9, D 0.0 (a6+1), D 1.5 (a5+1),	D  3.0 (a5), D  4.5 (a4)
5	R  7, D 0.0 (a6+1), D 1.2 (a5+1),	D  2.3 (a5), D  3.5 (a4)

Title: Re: QF guns for smaller ships
Post by: Islacrusez on August 24, 2013, 02:32:36 PM

Any thoughts, horizon?

Title: Re: QF guns for smaller ships
Post by: horizon on August 24, 2013, 03:00:27 PM

I see numbers. A lot of them.
;)


In some cases the bonus is quite high, the backlash of lower range takes it down a little.

I think some playtesting may be in order.

Fly some standard versions against QF versions in a 500pts battle.

Title: Re: QF guns for smaller ships
Post by: Islacrusez on August 24, 2013, 03:21:55 PM

Will need to run some lop-sided tests too, because the bonus against other escorts is significant; the downsides are the ineffectiveness against larger ships.

Title: Re: QF guns for smaller ships
Post by: ehlijen on September 04, 2013, 04:09:25 AM

What about saying Quickfire weapons simply treat escorts as capital ships for gunnery table purposes?

Ie, they'd get more shots against similarly small targets, but work exactly the same (apart from reduced range) against larger targets.

It's a nice and simple way to make them good at hunting smaller targets.

Title: Re: QF guns for smaller ships
Post by: Thinking Stone on September 06, 2013, 12:53:35 PM

Hello!
Unfortunately, I don't have the time to look through the detailed arithmetic you've provided, Islacrusez, but the general idea combined with ehlijen's suggestion reminds me a lot of my ideas on escort gunnery.

If one were to swap around the gunnery chart for escort weapons batteries (i.e. defences <=> ordnance, capital ships <=> escorts), I think it could represent the idea of batteries firing barrages of multiple, if smaller, weapons. Transports (etc.) would then be better at defending themselves against small raiders (as one might expect). As a corollary, escorts would need more dedicated weapons for tackling capital ships and defences (i.e. lances and torpedoes), kind of dividing them up into different role-classes based on weapons.

I think this swap would be a bit faster in both thinking time (once you'd become used to the system) and dice-rolling time (less re-rolls) than your idea... it would be interesting to compare damage output (unfortunately, I don't have time at the moment, but it's quite easy to work out).

(not intended to be advertisement for my own ideas :) I just thought I could contribute :) )

Although I have wondered about such re-rolling mechanisms... as long as there aren't armour modifiers, they are relatively linear in most circumstances (they can be a bit tricky if there are modifiers like in Epic: Armageddon, where Eldar lances were supposedly quite swingy with the same mechanic as in BFG).

Food for thought,
Thinking Stone

Title: Re: QF guns for smaller ships
Post by: Islacrusez on September 06, 2013, 11:44:14 PM

If you really want to fry your brain, try porting this to Rogue Trader ><