QF guns for smaller ships

[Islacrusez]

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!

[Islacrusez]

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.

[horizon]

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

[Islacrusez]

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.

[horizon]

Good, less imagine. Six Iconoclasts for 180pts.

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?

[Islacrusez]

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.

[Cneo]

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.

[Islacrusez]

Good, less imagine. Six Iconoclasts for 180pts.

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.

[Islacrusez]

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.

[Islacrusez]

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.

[Islacrusez]

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)

[Islacrusez]

Any thoughts, horizon?

[horizon]

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.

[Islacrusez]

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.

[ehlijen]

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.