Spaceships and ROF

[d_ns]

Seems all I ever do is post odd questions about the rules in Spaceships here...

Bottom of p.57, all identical fixed mount weapons in the same battery may be fired simultaneously - multiply ROF by the number of fixed mounts.

If you're talking about a weapon that is already VRF, flining out 200 20mm shells at a time, is there really any benefit, other than reduced number of rolls, to doing so? Or have I just reached the point at which the default GURPS ROF rules begin to lose their flavor?

[Ulzgoroth]

Originally Posted by d_ns

Seems all I ever do is post odd questions about the rules in Spaceships here...

Bottom of p.57, all identical fixed mount weapons in the same battery may be fired simultaneously - multiply ROF by the number of fixed mounts.

If you're talking about a weapon that is already VRF, flining out 200 20mm shells at a time, is there really any benefit, other than reduced number of rolls, to doing so? Or have I just reached the point at which the default GURPS ROF rules begin to lose their flavor?

Adding together RoF is almost always disadvantageous, compared to firing the same number of shots as more attacks at the same base skill level.

The one advantage of a combined volley is that it allows a single gunner to fire more weapons. You can only make one attack per gunner after all.

[d_ns]

Originally Posted by Ulzgoroth

The one advantage of a combined volley is that it allows a single gunner to fire more weapons. You can only make one attack per gunner after all.

Searching my PDFs mentions that the gunner can be a computer - does that imply only an AI of some level, or can you slave point defense guns to computer/sensor combo and let them do the shooting?

[starslayer]

Originally Posted by Ulzgoroth

Adding together RoF is almost always disadvantageous, compared to firing the same number of shots as more attacks at the same base skill level.

The one advantage of a combined volley is that it allows a single gunner to fire more weapons. You can only make one attack per gunner after all.

The one exception to this is when your skill for that shot is dangerously low (due to range, ECM, etc)- since large bursts get a higher bonus to effective skill it can turn a 7 to a 9 or a 9 to an 11 to fire all at once, which can be huge in terms of the 3d6 bell curve.

[Ulzgoroth]

Originally Posted by d_ns

Searching my PDFs mentions that the gunner can be a computer - does that imply only an AI of some level, or can you slave point defense guns to computer/sensor combo and let them do the shooting?

An AI, essentially. It's meaningless systemwise for something with no defined level in the applicable skill to be doing the shooting, after all.

Logically, it should be possible to have a very low intelligence and low complexity gunner program. The rules as they are would suggest modeling that as a sub-sapient, dedicated AI, though you could make up a non-character program that does the job at some specified skill level.

If your setting permits you to load a bunch of low-complexity but accurate gunnery AIs into your ship's network, you'll probably want to do so and have little use (or space) for human weapon operators.

Originally Posted by starslayer

The one exception to this is when your skill for that shot is dangerously low (due to range, ECM, etc)- since large bursts get a higher bonus to effective skill it can turn a 7 to a 9 or a 9 to an 11 to fire all at once, which can be huge in terms of the 3d6 bell curve.

I think you may need to go lower than you realize. +2 RoF modifier roughly corresponds to 4x as many shots, right? 4 rolls at 9 has a much better chance of landing at success than one roll at 11, though I'm not sure right off how they compare on expected number of hits.

[d_ns]

Originally Posted by Ulzgoroth

If your setting permits you to load a bunch of low-complexity but accurate gunnery AIs into your ship's network, you'll probably want to do so and have little use (or space) for human weapon operators.

So old school Traveller, with their targeting programs, would be one example of this, I'm guessing.

I think you may need to go lower than you realize. +2 RoF modifier roughly corresponds to 4x as many shots, right? 4 rolls at 9 has a much better chance of landing at success than one roll at 11, though I'm not sure right off how they compare on expected number of hits.

+1 ROF = 2x the ammo expendature, so we're looking at losing ground when 6- becomes 7- (9.3 and 16.2% respectively).

[Jovus]

You could house-rule that RoF gets divided by 100, minimum 1, when determining how many shots hit due to recoil.

[Ulzgoroth]

Originally Posted by Jovus

You could house-rule that RoF gets divided by 100, minimum 1, when determining how many shots hit due to recoil.

I'm not sure exactly what you're suggesting here, but it sounds very strange.

[Jovus]

Originally Posted by Ulzgoroth

I'm not sure exactly what you're suggesting here, but it sounds very strange.

If you wanted a more cinematic game where more bullets hit for high RoF guns, figure out how many bullets hit per recoil interval by dividing RoF by n.

In the example I gave, n = 100. So, if you have an ROF 500 gun, divide the ROF by 100 and get 5. Let's say this same gun has a recoil of 2. So, for every +2 you made the roll by, 5 bullets would hit, instead of 1.

Change n to change flavor. 100 will give you mostly-realistic, and some might argue moreso, for truly insane RoF. If you change n to, say, 20, this makes it so that master marksmen can hit with nearly all the bullets of nearly any gun if they get critical successes.

[vierasmarius]

Originally Posted by Ulzgoroth

I'm not sure exactly what you're suggesting here, but it sounds very strange.

What he's suggesting is that, for spaceships with RoF over 100, you multiply the Margin of Success by RoF/100 to determine number of hits. In other words, RoF 200 gives 2 hits per MoS/Rcl, RoF 300 gives 3 hits per MoS/Rcl, etc. If doing this, I'd also cap the Rapid Fire to-hit bonus at RoF 100. Otherwise, you'd have effective hit rate go up at RoF 200+.