Changing Rapid Fire

[sir_pudding]

Originally Posted by Ulzgoroth

However, he does seem to have dropped the target size modifier, unaccountably, so this is mostly right. However, skill 27 only results in all 20 shots hitting if you roll a MoS of 19 or better, which requires rolling an 8 or lower. Not impossible, but no sure thing. Even with the Rcl 1 weapon.

Except each of the shots that missed then apparently are under Hitting the Wrong Target and unless something else is in the line the fire the only things on either side of the target point is more BSG.

Or you can suppress the other side of the ship.

Really the problem here isn't the rules for attacking point targets, it's the lack of rules (other than Suppression Fire and Explosions) for engaging area targets.

[Kallatari]

Originally Posted by Langy

Those rules actually don't apply if the target isn't completely immobile; they only apply to things like hitting the broad side of a barn, or the ground, not a gigantic vehicle, even if the vehicle isn't moving fast enough to affect whether or not it's hit. Further, it's completely against the whole 'RoF is about hitting a point-target' idea.

Personally, as a house-rule, I removed the "immobile" restriction and instead said "if the SM minus the Speed penalty of the target (from Range/Speed table) completely counteracts the Range penalty, then you hit with half the shots on a success, and full shots on a success by Rcl. So, if that +20 SM ship is moving at 10 y/s (-5), the rule applies if you're within a range that only has (20 - 5 =) -15 or better range penalty to hit." And yes, we're talking relative speed.

To counter the fact that, with my house-rule, you can now use this on a human at point-blank range even if he's not immobile (as long as he's not moving too fast), if you're in close combat with the target, his Dodge is improved to match this rule, in which an exact Dodge avoids half the rounds, and a Dodge by 1 or more avoids all the rounds.

Finally, if in close combat, let's not forget the option to "parry" the gun, effectively deflecting the barrel and causing a wide miss. With this, a successful parry by any margin causes all the rounds to miss as well. As far as I'm aware, this parry option is actually RAW (but would have to look that one up to prove it). Regardless, this also helps balance out my house rule.

Otherwise, as a couple people have already said, we're talking about an extreme limit of the rules in which the GM just needs to overrule any strange effect he doesn't like. Otherwise, you have the stupid possible game effect of "I throw my knife to hit the ground. Roll to hit; 18, critical failure, so complete miss. Oh well, guess my knife went off into space if it didn't hit the ground." As a GM, I wouldn't even require a roll for throwing the knife because there is no way to miss the Earth (unless I was playing a Hitchhiker's Guide to the Galaxy campaign). I likewise don't roll to see if the walls behind my targets are hit by stray bullets; they are. With the often-quote battleship at close range from others in this post, I'd just rule that you hit. It's why these games have a GM.

[Phoenix_Dragon]

Originally Posted by vicky_molokh

The target is 1500yds wide. The range is 2000yds. The shooter is abnormally skilled. And 19 out of 20 bullets (maybe all 20) will fail to hit this 1500-wide target. 95% of bullets will go 750yds (375 if we include shorter sides) to the side at 2000yds. With a Rcl 1 ('recoilless') weapon.

For a pilot who can't be bothered to take a single second to aim, with no targeting systems or aids, aiming at a one-yard circle at a mile? Sure. It's only his absurd skill that let him do even that. He should count himself to be incredibly lucky.

Because if he were shooting at Gallactica, with its SM+17, 1,500-yard bulk, he would have hit with 90% of his rounds. So what's the flaw you're trying to point out?

(You entirely dropped the target's SM from your workup, there)

And with the houserule I mentioned, he'd make that hit with every round with a skill of only 17 on a roll of 10. Again, for a completely unaimed shot at a mile. Take a single second to aim, with even a basic targeting system, and even a raw recruit could make that shot.

[vicky_molokh]

Found errors in old example, rehashing it:

Get, say, a BSG Viper. Its cannon has RoF 20/second, or 400 per 20-second round in GSS. It is roughly SM+4. Give it Rcl 1 for the fixed mount, we're feeling generous.
In a training exercise, let it target the BS-F-G, 1½km in length (SM+17).

Both ships are moving at a constant speed, and relative speed is not zero. The absolute distance mod is greater than absolute size mod (1 mile vs 1500yd), so we get speed mods but no dodge.

Under Basic Set rules, that means that while they're both in flight, an unaimed, not electronically aided attack (they're afraid of Cylons taking over the targeting computer!), with base skill 20 (cinematically good), +4 (for RoF 20), -18 for range and +17 for size, total 20+4-18+17==24-18+17==23. On a roll of 11 (pretty average), we hit with (23-11)+1==13 bullets out of 20.

The target is 1500yds wide. The range is 2000yds. The shooter is abnormally skilled (though not as good as in the erroneous example). And 7 out of 20 bullets will fail to hit this 1500-wide target. 35% of bullets will go 750yds (375 if we include shorter sides) to the side at 2000yds. With a Rcl 1 ('recoilless') weapon.

Now, let's say we install some experimental Ultra-Vulcan cannon onto the Viper instead of its normal one. Let's say RoF400 (+9 to hit).

Same rolls: Skill 20+ RoF Bonus 9 + 17 size - 18 range == 28. That should be a lot of bullets into the BSG. Right? Nope. A roll of 11 with modified skill 28 means (28-11)+1 == 18 hits. That's 4½%.

Oh wait, let's add some targeting software. Acc 30? Sure!
So now, Skill 20 + RoF bonus 9 + size bonus 17 - range penalty 18 + Acc 30 == 58. Lots? Lots.
A roll of 11 means (58-11)+1 == 48 hits. Still an underwhelming 12%. The rest of the bullets apparently went at the very least 375yds to the side. At 2000yds. So the majority of bullets go 18yds off-center for each 100yds travelled.

[vicky_molokh]

Regarding 'point targets':

RoF rules are definitely not meant to treat the target as being limited to a 1×2yds figure, otherwise they wouldn't accept Size Modifiers at all. A failed roll against a given SM means that the strike did not manage to land within the space occupied by said SM. Otherwise I would be allowed to shoot at the Eye hit location and then, upon missing, claim a reroll against every eye-sized hex on the opponent's body.

[Langy]

Originally Posted by vicky_molokh

Regarding 'point targets':

RoF rules are definitely not meant to treat the target as being limited to a 1×2yds figure, otherwise they wouldn't accept Size Modifiers at all. A failed roll against a given SM means that the strike did not manage to land within the space occupied by said SM. Otherwise I would be allowed to shoot at the Eye hit location and then, upon missing, claim a reroll against every eye-sized hex on the opponent's body.

No, the rules do treat it as a point target, but only after the first shots have hit; ie, if you aim at an SM+15 vessel, you don't care where on the ship it hits, only that it hits within a 1 yard radius point target.

And no, that assumption doesn't make much sense.

[vicky_molokh]

Originally Posted by Langy

No, the rules do treat it as a point target, but only after the first shots have hit; ie, if you aim at an SM+15 vessel, you don't care where on the ship it hits, only that it hits within a 1 yard radius point target.

And no, that assumption doesn't make much sense.

If it hits within the 1 yard radius (from center of mass, I assume), then why does the ship being large help me hit that 1 yard radius?

Also, it would mean that when I attack an SM+9 target, I get to claim the +9 bonus for SM and the right to land my shots in an SM+0 target (which happens to match the default eye size of an SM+9 entity).

[Ulzgoroth]

Originally Posted by sir_pudding

Except each of the shots that missed then apparently are under Hitting the Wrong Target and unless something else is in the line the fire the only things on either side of the target point is more BSG.

Or you can suppress the other side of the ship.

Really the problem here isn't the rules for attacking point targets, it's the lack of rules (other than Suppression Fire and Explosions) for engaging area targets.

Actually, the rules for attacking point targets can't possibly be right either. Consider, if you will, that we could simply scale the carrier and distance down until it's a few yards away and roughly human-sized. 2 yd target 3 yd away. It is now a point target, but both the net modifiers and all the geometry is basically the same.

The scaling just isn't right. It could be close to right for point targets at some particular range, but not at all ranges.

And of course allowing suppression fire or bullet scatter to argue that all your shots go somewhere near where you want with no roll would make AA machineguns or autocannon a bit too accurate.

[Langy]

Originally Posted by vicky_molokh

If it hits within the 1 yard radius (from center of mass, I assume), then why does the ship being large help me hit that 1 yard radius?

Because you don't care which one-yard radius you hit; it most certainly is not 'from center of mass'.

[DouglasCole]

http://forums.sjgames.com/showpost.p...5&postcount=12

This alludes to a PDF and PPT file that basically gives scatter for shots if you want it. Implementing this in a pen-and-paper RPG would take work, but . . . with the addition of a "where does it go" roll (and if you have a computer, you might as well use 360 degrees instead of d12 for 30 degrees), you could basically define the center of the target area you're aiming for with as much precision as you like, and misses will scatter in a random direction, displaced from the aim point based on margin of failure.

With the right target (an elongated box in the BSG example), you could have each shot hit where it hits.

Once I get through a few other things (Technical Grappling final draft, a Pyramid article I'm working on, etc), I might return to this. Finding a simple way of doing this (where do the spare shots go?) against the GURPS point-target assumption based on margin of failure would take work and probalby run into its on set of Murphy's, but would solve the issue OK.

dhc