Automatic fire with Area of Effect, How does one handle this? Options Track this topic Email this topic Print this topic Download this topic Subscribe to this forum Display Modes Switch to: Outline Standard Switch to: Linear+

[Togashi Shinjits...]

Full-auto and Burst-fire Area of Effect weapons are not handled by the Shadowrun rules.

(if you think full auto grenade launchers are not here already search for - Mk19, XM307, XM25 (for the MGL-12), Metalstorm's Redback to name a few)

Imagine this scenario: A short burst from a grenade launcher at a target. (grenade launcher is equipped with airburst option)

Narrow burst - all grenades are aimed at the same target. If you hit, they all hit the target, doing standard +2DV for a burst.
(If you miss, it would be reasonable to assume that the entire burst scatters as one entity.)

That works, but here come the problems

Wide burst - the grenades are fired in the general direction of the target, aiming to catch the target with ONE of the grenades at least.

If you hit with a wide burst, ONE of the grenades hits the target. Where are the other two? If they aren't on target, they scatter, which is reduced by hits, so they will hit as well. this brings them up to standard +2DV per extra shot hitting again.

Damage from Wide Burst that hits = Narrow Burst that hits, but it is harder to dodge. Rules fail.

If you miss with a Wide Burst, NONE of the grenades are on target, but scatter as grenades do. Airburst grenades scatter by 1d6 metres, and if you use fragmentation grenades, they have a 12m blast radius. The target is hit by the blast from 3 separate grenades, even though you missed. How do you figure out the DV for that? One grenade may be 5m away, one may be 1m away, and one may be 3m away. Rules fail.

If the burst scatters as a group instead, how does a Wide Burst differ from a Narrow Burst? Anyone caught in the blast would be affected as if they were shot with a Narrow Burst, not a Wide Burst. Rules fail.

These problems are exaggerated when you look at Full Bursts or multiple targets. Within a metre of each other? If you hit them with a grenade, they will be caught in the AoE at a metre distance. They are pretty much still the target. Does it mean that the blast radii can be up to a metre apart?

What about suppressive fire with a Full-auto AoE weapon?
20 rounds downrange (10m width at end of range) from one action phase to your next action phase. That is SERIOUS destruction. Bullets are easy to track in that kind or scenario. They end up imbedded in something. Airburst grenades don't. They do a LOT of collateral damage, and you can't figure out where it should happen. Rules fail.

What about 4 initiative passes firing Full-auto suppression? 80 rounds downrange in 3 seconds. Even over a 40m spread, that is untold destruction with AoE weapons.

The closest to Full-auto AoE weapons in the books is the Fleche missile barrage system. Which is freaking rules heavy if you adapt them to use on every Full-auto AoE weapon. separate to hit rolls for each one? Up to 20? for each missile past the first, apply a -2 dice pool modifier to the to-hit roll.
so the first one will be on target, the next ones may not be so lucky...

[BlueMax]

(if you think full auto grenade launchers are not here already search for - Mk19, XM307, XM25 (for the MGL-12), Metalstorm's Redback to name a few)

I know they are here. However, they are likely not in the rules because of balance, or were not appropriate for the setting.

[Draco18s]

Likely balance. I've shown (in another thread) that one grenade takes down walls. You start throwing 3, 5, 10 of them down range there ain't gonna be nothing left.

[Togashi Shinjits...]

Likely balance. I've shown (in another thread) that one grenade takes down walls. You start throwing 3, 5, 10 of them down range there ain't gonna be nothing left.

Yes, grenades are destructive. That is both a boon and a bane.
Balance is maintained in the same way as every character doesn't walk around with 2 suitcase rocket launchers at all times.

Perhaps they aren't appropriate for a given game setting, but we are running a mercenary game, and as such we need some anti personnel/ light vehicle weaponry that is filled perfectly by a full auto grenade launcher mounted on the 2070 version of a HummVee.

But then, when are ship mounted gauss cannon and lasers that can dazzle satellites going to be part of many game settings? (ignoring that railcannon are less troublesome than gauss cannon).

Would adapting the Fleche barrage mechanics to suit be a reasonable compromise?

I'm looking for solutions and suggestions (IMG:style_emoticons/default/frown.gif)

[Shinobi Killfist]

Normally I'd suggest hitting the player wanting this idea with a big stick as a solution, but I guess that wont work in this situation. I'd say just play the autofire rules straight, don't think about the logic of it.

Wide burst -X to dodge. Bo extra damage. It only hits one grenades worth of area well enough to do damage.
Suppression fire an area is hit for base grenade damage and that be it, they get reaction +edge to try and grab cover to avoid the damage.

Its a RPG it does not have to make sense. And heck the rules already don't, so why sweat whether this one makes sense.

[Draco18s]

Well, characters already don't dodge grenades (great, the grenade you were dodging--instead of impacting your chest--impacted the floor behind you. You still take N damage).

Narrow Burst: +X to damage. (+X to AP for frag)*
Treat scatter and area of effect as normal.**

Wide Burst: -X to the scatter roll (die pool for scatter remains the same, subtract from the result).

Still treat the wide burst as a single area effect, only subtract X from the scatter result (treat it as extra hits on the "hit the mark" test). You're throwing grenades EVERYWHERE, one of them is going to be right where you want it (ex. throw a fist full of pennies at a coffee cup from 20 feet and count how many land inside, now take 1 penny and try to land it in the cup).

*Might be worth +2X (ie. a short burst is worth +4 damage (+4 AP)) due to the general effectiveness of grenades; a off-target narrow burst should still be more damaging than a no-miss wide burst.
**Added DV does not increase area, similar to the burst damage modifier not being added in when determining stun vs. physical against armor

[Togashi Shinjits...]

I've spent hours hammering this out, and have come up with this so far:

Narrow burst = scatter as 1 unit, +2X to damage (we used the rationale of +1DV per extra shot on target, +1DV from the sympathetic detonation rules in Arsenal) AOE is as for 1 grenade. -(x-1) for recoil of burst.

e.g. you are 6m from a narrow burst of 3 frag grenades. Modified DV is 16 at impact, 10 (6+4) at your location.
If you were 12m away, you would escape the blast (AOE is determined using DV of 12, not 16)

eg you are 4m from a narrow burst of 6 HE grenades. Modified DV is 20 at impact, 12 (2+10) at your location.
If you were 5m away, you would escape the blast (AOE is determined using DV of 10, not 20)

Wide burst = Scatters as 1 unit, Damage is base from impact point, but Blast dropoff changes by a factor for every 3 rounds.

i.e. for frag, dropoff changes to:
-1 per 2m given 3 rounds,
-1 per 3m given 6 rounds and
-1 per 4m given 9 rounds.

for HE, dropoff changes to:
-1 per m given 3 rounds,
-1 per 1.5m given 6 rounds and
-1 per 2m given 9 rounds.

e.g. you are 6m from a wide burst of 3 frag grenades. DV is 12 at impact, 9 (12-(6/2)) at your location.
If you were 12m away, you wouldn't escape the blast, suffering a 6DV hit (12-(12/2) at your location.
You would need to be 24m (12-(12-24/2)) away from the target point to avoid taking shrapnel.

eg you are 3m from a wide burst of 6 HE grenades. Modified DV is 10 at impact, 8 (10-2) at your location.
If you were 5m away, you wouldn't escape the blast, suffering a 7DV hit (10-3) at your location.
If you were 6m away, it would be a 6DV hit (10-4).
You would need to be 10.5m (10-10) away from the target point to avoid the blast.

It means that wide bursts will usually catch their target unless they have cover, or are INSANELY good at dodging.
It also does Stupid™ amounts of collateral damage that you can't control. Not a good thing in confined spaces.

Targets may be up to 10m apart for multiple targets (means a narrow HE burst won't hit 2 ppl next to each other)

Suppressive fire is still tricky though. 20 rounds downrange is heavy fire for any situation, and the collateral is pretty hefty.

Probably just reduce the number of rounds fired to 5.

If the target in the suppressive fire field makes the threshold, they avoid a blast. If they don't make the threshold, move a blast at maximum scatter towards them by the number of hits they missed by.

e.g. Joe Shmoe ducks from his trench and makes a break past the Humm-Vee covering his position with the Auto Grenade Launcher.
The gunner got 4 hits on his area suppression roll. Joe needs 4 hits on his dodge test or he risks a lethal helping of high velocity shrapnel.
He rolls (with -2 dice due to AOE weapons) and gets 3 hits. Ow. Not good enough. He is caught in a blast from one of the airburst Frag grenades.
He is 6m (maximum airburst scatter) -1m (missed hit) = 5m from ground zero. He suffers a (12-5) = 7P(f) hit. His Flak vest turned out to be worth something after all.

If he had made the threshold, he would have dodged the blasts completely. If the grenades hadn't been airburst grenades, they could have ended up 17m away, and he would still have been safe.
If they had been HE grenades, 5m is just outside the blast radius. Frag grenades are worth it for area suppression.

[Draco18s]

Actually, those aren't bad wideburst rules. Increasing the AOE.

Our group also decided that the Chunky Salsa rules are stupidly broken (i.e. a dude next to 1 wall 0m away from a grenade--even frag--just dies: 24P(f) ). Maybe it should be errata'd that frag grenades don't chunky salsa. (I mean shrapnel reflecting off a brick wall, yeah right).

[Dream79]

In the case of a frag which is still explosive I would take 4/6P off the rebound to reflect the +2/+3 damage mod constituting the the frag party favors. This would mean that the rebound would cause 20P(f)/18P(f) of which I lean towards the +3 damage modifier so it doesn't make the HE grenade pointless. Even if the PC/NPC is within one meter of the barrier the blast could still be considered to have traveled 2 meters, at least IMHO.

On edit: Shouldn't armor be applied twice as well? Just a thought.

[Draco18s]

In the case of a frag which is still explosive I would take 4/6P off the rebound to reflect the +2/+3 damage mod constituting the the frag party favors. This would mean that the rebound would cause 20P(f)/18P(f) of which I lean towards the +3 damage modifier so it doesn't make the HE grenade pointless. Even if the PC/NPC is within one meter of the barrier the blast could still be considered to have traveled 2 meters, at least IMHO.

+3 damage modifier? From what?

And yes, 1m away from a wall is a 2 meter difference in waves. However a character less than one meter (say, a guy leaking on a wall) is 0 meters away, thus the rebound distance is 0*2 = 0. Standing/fighting you might get away with fudging that up to a full meter.

On edit: Shouldn't armor be applied twice as well? Just a thought.

It's not. You add up all the waves hitting the character and make one damage resistance test.

[Dream79]

+2/+3 being the typical damage modifier of flechette which fragmentation is treated as.

I think in some ways the fudging is implied since a meter in a RPG typically is not a true meter like in the real world but a hex. There's no way to factor 56cm for instance so it's either treating 56cm as 0 meters or 1 meter. Personally I would GM it as one meter unless a)the character is lying on the explosive and the barrier is the floor/ground or b) the explosion occurs in front of a character leaning against the wall so no rebound at all, but would effect another character 1 meter in front of him.

So my reasoning is that in the case you describe I would consider it a meter meaning the rebound has a 2 meter falloff. When factoring in that for mechanics purposes flechette likely means a +3 damage modifier calculated into the 12P(f) and the fragments wouldn't likely rebound. So loosing 5P (cough, oops) seems reasonable.

On edit: I usually avoid using a hex maps in my games but it fits 'game logic'. Since the barrier typically occupies another hex and the blast is traveling into the hex, typical hex map mechanics figure the target of an attack in a hex to be the farthest point of that hex for purposes of range. Using this logic the a) and b) conditionals I used would actually be fudging in this case.

[Prime Mover]

I've tried to keep this simple. One roll for scatter. Add one meter to effect for each grenade in the burst. Adjust damage value as you would normally.

Even simpler treat it as normal burst fire rules with a 10 meter effect.

Resistance as with normal grenade attacks.

As for it not existing in SR at all, with arsenal you can adjust the Armtech MGL series for burst fire?

A recent example ended up with a full auto burst being fired at a target. Damage being 19P -2AP with a 19 meter blast radius (full auto HE) before resistance tests.

[jago668]

I always just said scatter like normal and resolve the 1, 2, 3, 6 whatever number of grenades seperate. Meaning you would take X x 10P-2 -2/m hits, where X is the number fired. The reason is that you fire a 3 round burst and do one 12P-2 -2/m hit, or you can fire semi-auto and do 2 x 10P-2 -2/m hits. I know which one I would rather have, and it expends less grenades. Especially since burst/full auto don't modify the DV for armor comparison.

[Togashi Shinjits...]

I've tried to keep this simple. One roll for scatter. Add one meter to effect for each grenade in the burst. Adjust damage value as you would normally.

Even simpler treat it as normal burst fire rules with a 10 meter effect.

Resistance as with normal grenade attacks.

As for it not existing in SR at all, with arsenal you can adjust the Armtech MGL series for burst fire?

A recent example ended up with a full auto burst being fired at a target. Damage being 19P -2AP with a 19 meter blast radius (full auto HE) before resistance tests.

That doesn't really work with the blast drop-off rules for AoE weapons. Unless you are suggesting a central AoE of constant DV?
It also doesn't take into account the difference between Wide and Narrow bursts. How would you deal with Suppressive fire using these rules?

My example may seem a little complex, so I am still looking for something simpler.

I tried looking at the scatter like normal and resolve 1,2,3,6 etc individual rounds, but that turns autogrenade launchers into mega bad engines of death that take 40 minutes to work out the damage from a single burst. I'm trying to find the middle ground between "Full Auto AoE superkilla doom that will keep you there all night rolling damage", and "grenades are just big bullets, roll once".

Something that reflects the deadly effect of full auto grenade fire, but without individually dealing with every impact.

Slightly OT, Chunky Salsa can be problematic, but to make it easy on yourself, only use it when the blast is confined somehow. Only use it when more than 3 of the six faces of a surrounding box are blocked. i.e., not when you have the floor, one wall and the roof (like under an overhanging balcony), but use it when you have 2 walls, roof and floor (like in a corridor). Also remember that the shockwave only bounces if it doesn't breach the barrier.
Most explosions will go through walls pretty easily. A door (barrier 6) won't stop a frag grenade a metre away from blowing a hole in it (DV 12 vs armour 6, AP is ignored for damaging barriers), but it WILL stop the explosion from reaching the other side (destroying barriers still gives things on the other side of them their armour rating, in this case 11, 6 for the door, and +5AP for it being a frag grenade)
different story if the grenade is directly against the door, but you get the idea...

[Wasabi]

The easiest way to handle them is to have your players ban it from the table. Simply use full-auto AOE weapons *against* the runners and when your players roll new characters suggest they choose not to have them either. M.A.D.*!
Also bear in mind only certain feed mechanisms can support autofire. Many grenade launchers are fed like pump-action shotguns or revolvers and you aren't going to see a full auto weapon that doesn't use a box-style magazine. So for example, the pulse rifles from the movie Aliens could not be modded for autofire since the fire selection change mod says its not available for weapons "using unusual loading mechanisms or exotic ammunition"

Heck you could also say grenades are exotic ammunition.




(* = "Mutually Assured Destruction")

[crizh]

On the chunky salsa thing, realistically someone leaning against a wall would not experience it at all.

The wavefront is stopped by his body and the rest of it does not have time to diffract before striking the wall. Just like in Hiroshima he casts a shadow on the wall behind him.

On topic, why would you use the Autofire rules for grenades?

Grenades are resolved with a completely different mechanic to Firearms. Why would you even consider using their Autofire rules? Rockets are resolved using the Grenade rules, a Fleche launcher is a rocket system. Use the Fleche rules.

As to Suppression Fire, it has no rules for insufficient ammunition. If you don't have 20 rounds you can't do it.

[BIG BAD BEESTE]

Interesting. I liked the point about auto grenade launchers not being available whilst railguns and ANDREWS naval weapons are. Have to agree with crizh there too - the autofire rules were designed for solid slugs, OK and possibly good old buckshot from your auto-shotguns out there, using them for area effect weapons such as grenades shouldn't work the same. You're not really going to damage a target more but autofire would cover a larger area, so using the larger area of effect at the grenade's basic DV would be acceptable compromise. I'm thinking of the fuel-air explosives here - they saturate the area inflicting the same damage throughout - more FAEs means a larger area but not really any increase in damage. Alternatively there's the explosives rules whereby more explosives does increase the potential blast radius and destruction but its dealt with as a single "attack". these are the options I suggest if you want to keep the maths and paperwork down to a minimum and get on with the game.

As for autofire grenades and suppression fire, well a single grenade is normally enough to "herd" targets away from its blast zone. More than a couple and you've got yourself an artilley barrage that should send everyone ducking for cover tout suite.

[Straight Razor]

what ever happened to the 3ed suppressive fire rules. they would apply to you wide burst just fine. only thing you would need to change is the 1 bullet per m^2 minimum. 1 gernade per 7 m^3 (one every 3m) should be just fine.