Different Gyroc Designs

[Fred Brackin]

Originally Posted by Ulzgoroth

Laser designator homing has the rather huge problem that you have to keep laying a laser designator on the target. UT targets will likely detect the laser and trace it back.

Not in less than one second they won't. Use the right ammo type and they'll be out of the fight after that one second.

Even if you have to make a"to ht" roll for the designator doing it with an ACC 6 laser instead of an ACC 0 gyroc would be progress. It alos takes care of the "gyrocs are unstable at low speeds" problem and as long as you're using a payload attack instead of a KE projectile you don't even care about the reduced KE damage.

[Ulzgoroth]

Originally Posted by Fred Brackin

Not in less than one second they won't. Use the right ammo type and they'll be out of the fight after that one second.

Even if you have to make a"to ht" roll for the designator doing it with an ACC 6 laser instead of an ACC 0 gyroc would be progress. It alos takes care of the "gyrocs are unstable at low speeds" problem and as long as you're using a payload attack instead of a KE projectile you don't even care about the reduced KE damage.

Less than one second? Why are you limiting your shooting to less than one second of projectile flight time?

[Anthony]

Originally Posted by Ulzgoroth

UT targets will likely detect the laser and trace it back.

The problem is less "trace it back" than "take it as warning that they've been detected and move behind cover or take other countermeasures".

[Varyon]

Originally Posted by Ulzgoroth

You're trying to get the target's velocity. You need to get at least two separate datapoints with both range and bearing information (and time) to be able to do that.

There's the moment it enters your rangefinder's line of sight, and the moment it exits. This won't truly give you velocity, as your rangefinder would need to know the target's length, but it will be enough to tell you where to aim to hit the target (because if it's 1 yard long and traveling at 10 yards per second and you set your weapon to hit in the dead center, it would also hit in the dead center if the target were 10 yards long and traveling at 100 yards per second).

Originally Posted by Ulzgoroth

On a basic qualitative level, saying that artillery gunners, siege engineers, snipers, and tank gunners engaging stationary targets have no use for rangefinding is egregiously wrong.

I agree, but the alternative is that rangefinders magically make the target 3x its actual size for purposes of hitting it. Unless we want to create some system to create penalties based on need to account for bullet drop and leading the target.

As it turns out, I just made such a system, and a thread to discuss it.

[Ulzgoroth]

Originally Posted by Varyon

There's the moment it enters your rangefinder's line of sight, and the moment it exits. This won't truly give you velocity, as your rangefinder would need to know the target's length, but it will be enough to tell you where to aim to hit the target (because if it's 1 yard long and traveling at 10 yards per second and you set your weapon to hit in the dead center, it would also hit in the dead center if the target were 10 yards long and traveling at 100 yards per second).

...No? That makes no sense at all?

That doesn't even give you enough information to aim at its centerpoint, because you don't know how many degrees between the center and the trailing edge (and you don't know where the leading edge is).

And wherever you aim, after say 5 seconds of flight time the 450 yards difference in position between the two proposed objects means it's impossible that the the same shot would hit the center of both of them, or indeed hit both of them at all.

Originally Posted by Varyon

I agree, but the alternative is that rangefinders magically make the target 3x its actual size for purposes of hitting it.

You're probably not wrong to criticize the plus three, but that's a terrible criticism - you could write the exact same criticism of any bonus.

[Rupert]

Originally Posted by Varyon

At what point do you feel the full bonus (+3) is appropriate? If we have a decent value there, we could come up with the ranges at which it would get +1 and +2. For example, if +3 is appropriate at 2000 yards, that's normally -18 to hit, indicating a +1 for every -6 is appropriate. Of course, now that I think on it, there's probably no range at which the +3 bonus is appropriate - an SM-6 target 10 yards away looks the same (in a featureless plane) as an SM+12 target 10,000 yards away, and indeed both are at -10 to hit. It's kind of hard for a rangefinder to give you better hit chance than a same-size (by perception) target that's close enough that time-to-target doesn't matter. If may be more realistic to only allow a rangefinder to reduce any penalties due to the target's speed (or introduce a rule that gives time-to-target penalties, and let rangefinders reduce those).

A 'rangefinder' doesn't help you with target speed at all. For that you need some kind of ballistic computer.

I'd say that a rangefinder's bonus can only counter range penalties, and seeing as knowing the range could be useful at as little as 200 yards for some rifles, and less than that for bows, I'd be inclined to just let it go at that.

[Anthony]

Originally Posted by Rupert

A 'rangefinder' doesn't help you with target speed at all. For that you need some kind of ballistic computer.

It's a very simple mechanical calculation: if you know the range, you need to lead the target by an amount equal to the time required for your projectile to arrive. That's calculation that's doable without electronics.

[Varyon]

Originally Posted by Ulzgoroth

...No? That makes no sense at all?

That doesn't even give you enough information to aim at its centerpoint, because you don't know how many degrees between the center and the trailing edge (and you don't know where the leading edge is).

And wherever you aim, after say 5 seconds of flight time the 450 yards difference in position between the two proposed objects means it's impossible that the the same shot would hit the center of both of them, or indeed hit both of them at all.

Each vehicle is moving at a rate of 10x its length per second (which your weapon's computer knows because it took 0.1 seconds between the front of it passing an arbitrary point in space and the back of it passing that same point). If you need to hit it dead-center with a 5-second-flight bullet, you aim 49.5x its length in front of it. The fact your rangefinder doesn't know how long the vehicle is in yards and how fast it's moving in yards per second doesn't matter, because the length of the vehicle is a perfectly useful metric.

Originally Posted by Ulzgoroth

You're probably not wrong to criticize the plus three, but that's a terrible criticism - you could write the exact same criticism of any bonus.

Yeah, the description's a little excessive, but given what the range penalty it's suffering by default represents (just its apparent size, not time of flight or bullet drop or anything else), there's nothing logical the rangefinding bonus could represent. It's just "you're more accurate because you know the exact distance."

Granted, the Acc bonuses of many weapons suffer a similar problem (the mechanical accuracy of a rifle only comes into play if the user is skilled enough to reach or exceed said accuracy, and that doesn't really happen with most humans), but at least "more precise weapon hits more often" doesn't seem as bad as a bonus that basically offsets a penalty that doesn't exist.


Granted, it's late, so I may have some braincells crossed and am speaking pure gibberish, here.

[Anthony]

Originally Posted by Varyon

Granted, the Acc bonuses of many weapons suffer a similar problem (the mechanical accuracy of a rifle only comes into play if the user is skilled enough to reach or exceed said accuracy, and that doesn't really happen with most humans), but at least "more precise weapon hits more often" doesn't seem as bad as a bonus that basically offsets a penalty that doesn't exist.

There's something to be said for most current weapon bonuses just being offsets that negate specific penalties, though it's reasonable to give a rifle bonuses just because of a high velocity projectile, long sight radius, and a stock.

[Ulzgoroth]

Originally Posted by Varyon

Each vehicle is moving at a rate of 10x its length per second (which your weapon's computer knows because it took 0.1 seconds between the front of it passing an arbitrary point in space and the back of it passing that same point). If you need to hit it dead-center with a 5-second-flight bullet, you aim 49.5x its length in front of it. The fact your rangefinder doesn't know how long the vehicle is in yards and how fast it's moving in yards per second doesn't matter, because the length of the vehicle is a perfectly useful metric.

Only if your system has a sensor that measures the length of the target. Which you didn't mention, and which is actually not necessarily trivial.

Originally Posted by Varyon

Granted, it's late, so I may have some braincells crossed and am speaking pure gibberish, here.

Overall it seems like a reasonable-ish criticism of GURPS' entire ranged combat ruleset, but a poor criticism of the rangefinder bonus in particular.