There are several weapons that IRL have negligible recoil, like rocket launchers, flamethorwers and lasers. Do they suffer normal recoil modifiers or is ther a differing rule I'm not aware of?

lasers do not. not sure about flamethrowers, but i think they do (and i doubt the negligible recoil anyways... you have to propel the fuel somehow, and iirc they have quite an impressive range and they fire some kind of gelatin-like substance... probably fairly heavy. kinda like a firehose.)

rockets are generally single shot anyways, so since you only get one attack with them per IP it really doesn't matter... there is no second shot to suffer recoil, and recoil doesn't do anything to the first shot.

you might be right about that.

Only one of two rocket launchers in the BBB is single shot, the other is semi automatic as is another one in the Arsenal.

Still no Burst/FA Rocket/Missle-Luncher?

Not off the rack. But you could mod it. Unfortunately the ammunition is a little expensive for a mere +2 DV

FA Lasers however would a) be stylish and b) effective and the higher rate of fire could offset the weird drawbacks of rain and fog.

Hell yeah, PULE-LASERS!

Because a missile/rocket launcher has a back draft they don't suffer from recoil. That being said I would be hesitant as a GM to allow to create a rocket launcher that shoots BF or FA. You would need a missile/rocket rack to pull something like that off, and I doubt your character could lift all that weight. Even a single round BF rocket launcher pack that fires say 4-10 rockets in one BF round would require a powered exoskeleton to fire. Most people can only carry 3 missiles/rockets at one time before starting being weighted down.

Just as a quick note: Most "recoilless weapons" don't eliminate recoil completely, they just eliminate the kickback. Bigger weapons usually still shake quite a bit. I wouldn't envy the poor soul having to fire a handheld FA rocket launcher...
Lasers are about the only weapon type that actually has no recoil.

The sonic rifle thingie doesn't have any either.
And Flame-Throwers?
Come on, how much Recoil does your super soaker generate? O.o
That can NOT be compared to what comes out of firemens big long thick hoses . .

True, but FA Rocket Launchers need not necessarily be man-potable. Drones and vehicles could also get an increase in firepower. If the GM does not rule the vehicle sufficiently heavy to completely ignore recoil, the lesser recoil of launchers could help.

@Stahlseele: Or Lasrifles & Hellguns

Totally forgot the sonic weapon.

M2 Flamethrower

capacity; 4 gallons fuel, nitrogen propellant.

fuel is napalm, which is a mixture of gasoline and a thickener, we'll say 6 lbs a gallon. it uses half a gallon a second, and kicks flames 132 feet. that's ~396 back-of-the-napkin-foot-lbs. which compares to a round of 9mm parabellum. it has SOME recoil. certainly more than your super soaker.

Also has like 3 times the range.

Flamethrowers aren't free of recoil, as mentioned. You just don't care too much about straying from your intended target point by 5-10 cm as that still lights them up quite nicely.
I forgot about the sonic gun as well. I've no idea how those would react, as AFAIK in RL those are only experimented with on a much bigger scale. Those things tremble quite a bit, although it's not comparable to actual ballistic weapons of the same size.

And I'm not up to snuff on my w40k fluff, but aren't hellguns just high-powered lasguns anyway?

Misconception! Photons do have weight! They do generate recoil when propelled from a laser device. Its just negligable

/threadjack

Yes, because all those micro-newtons of recoil are SO throwing off your aim!

Flechette Hail Barrage Rocket Launcher. Arsenal. Capable of dumping 20 rockets on to some poor fool from a quarter mile away.

No. Photons have exactly 0 mass. 1 unit of atomic mass is a proton, a photon is smaller than an electron (5.4 * 10^-4 u), so even if it did have non zero positive mass, the number would be so small as to actually not matter in Newtonian physics (which is what recoil is).

http://www.usatoday.com/weather/resources/.../photonmass.htm

Its far less than 1 unit of atomic mass, but it is still there. Enough of them fired simultaneously and eventually you get something.

Not to get into too many details but I modified a super soaker once by replacing the hand pumping with a CO2 canister. When I fired the weapon it had kick (about the same as a C7 (M16)). I also melted the nossel of the super soaker.

Like I said, even if it is non-zero it's so small to not make a difference at the macroscale.

Plus, if it's moving at the speed of light, it is massless, thus a laser has no mass.

Not a rocket launcher, but the first thing I thought of.

(I think it's a shoulder fired anti-tank shell launcher? Not sure.)



-karma

It also doesn't let gasses escape from the back like a bazooka does.

This is defiantly not recoilless.

I'm not even sure what exactly that is.
Do I see that correctly, a system that fires some kind of shock piston backwards to mechanically simulate the way rocket launchers reduce recoil? Just so you can fire absurdly big calibres without ripping your arm off? What'd you actually need that for?

By RAW, several weapons that are effectively recoiless (or should be) are not. The Ares Super-Squirt causes recoil, and by a strict reading, the Pain Inducer does as well ("lasers cause no recoil" wasn't introduced until Arsenal, and Errata hasn't changed that weapon).

I'm willing to give the gyrojet pistol a pass. since real gyrojet pistols have a minimum range. while the FN-AAL does not, apart from the mechanism in the rockets. In a real example, the initial shove down the barrel is comparable with a Nerf cannon - one could stop the weapon by jamming a finger down the barrel.

And is entirely crazy in my opinion...

It looks like someone built the nuke slingshot from fallout 3

Actually, you can pull off a convincing robotech/macross impression w/ the mini-drone launch rack (the one which holds 10 mini, or 20 microdrones) and launch them all at once. They do have those suicide drones in the heimdall missiles . And nothing stopping you from arming your little bugswarm w/ a grenades each.


Overall... most of the weapons I'm seeing listed only fire at SA or SS though. And I'd say most of them don't qualify for the modification to allow them to go full auto as they have unique loading/firing mechanisms. (lasers in particular)

Quite frankly... I'm rather disappointed that the rules make both the power packs themselves a low avail 12+ illegal item. After the gun itself is already an 18F for the lasers... I was hoping to try one out sometimes as a primary out of chargen... but a restricted gear quality for each power pack and the gun... ouch. You'd think there'd be legitimate uses for very high power compact power supplies at worst making them an 'R' item.

RE: High Impulse Weapon: Is it just me or is that thing totally unwieldy? It doesn't look like it was designed for man-portable operation.

It looked REAL unwieldy to me...
I am pretty sure that I would not want to use it, unless it provided SIGNIFICANTLY more options than are already available with modern military weapons...

Another ineresting aspect is that the Ares Screech Sonic Rifle has an aviability of 16 (no 'R', no 'F', just 16) but the powerclips that it uses have one of 14F; everyone can buy it but nobody can buy the ammunitions to use it.

Looks like those things slipped through the cracks.

Have you ever FIRED a "rocket launcher"? Or a flamethrower, for that matter? Neither is trully recoilless in the sense that there is no back-pressure or deviation of the barrel in firing. Basic physics: for every action there must be an equal and oposite reaction. If you use compressed gas to push liquid in one direction, the aparatus itself will receive push back. The effective amount is small, relatively speaking, but not unimportant. But since it's an area effect weapon firing a continuous stream, it's largely irrelevant in use. Now, a rocket launcher has a significant "kick" on firing, largely due to shifts in center of mass as the projectile moves and friction between the departing round and the tube itself; The actual ejection motor (be it the primary or simply a separation charge) will also have some minor effect on the launcher. In game terms, since the fastest rocket launcher I have seen is Single Shot (SS), it's meaningless in rules terms. But if you're planning an ambush, remember that the back blast from most "recoilless" weapons in an enclosed space (say, an apartment on the third floor) will kill the operator instantly. In the late 1970s and early 1980's, the US Army and Marine Corps had a wire-guided man-portable anti-tank weapon, the M-47 Dragon, whose "kick" was so severe, many soldiers accidentally crashed their missiles in training when their sights wound up pointed at the ground immediately upon launch. They eventually resorted to a very odd looking and uncomfortable braced firing posture which negated this tendancy sufficiently for them to regain control and keep the missile on target.

(OK, I will give you that Lasers are legitimately recoilless. IS there a non-vehicular laser that has a Semi Automatic ROF?)

For one of my submissions for the open call for Missions adventures I cooked up a BF laser prototype (the Ares Firestorm). It was all kinds of nasty in the right hands, but it was biometrically locked. I statted out and ran the numbers on a FA laser, and slowly backed away.

Edited to reflect the BF natrure of the beast, not the SA.

Actually all man portable Lasers in the Arsenal are Semi Automatic. BTW there also is a rocket laucher firing SA in the BBB.

I don't want to sound ignorant but... BBB??

Big Base Book, or Big Black Book. The Corebook of SR4.

The Dragon still exists, as far as I remember... Beast of a Missile... not as good as the TOW, but still...

Rockets are "truely" recoil-less because the push-back from firing isn't directed at the tube from which it's fired. That is, there's no confined space that the gasses push on, they simply fall out the back end.

Textbook, you're right. But the thread was asking about recoil modifiers, and game mechanics are essentially asking "How much deviation of the barrel occurs as a result of firing which would lead increased circular error probable with subsequent rounds in short order?" So if the thing kicks like a mule from the firer's perspective, text book is pointless in this context. Look at the MLRS artillery system, based on the M2 Bradley Infantry Fighting Vehicle and weighing in at 27.5 short tonnes. If fires rockets from open tubes, but an MLRS crewmember will still tell you it's a dramatic experience when those rockets leave. So while it is true there is none of the complex recoil absorbing aparatus found on conventional artillery, if you fired the thing in space, it would still send you tumbling. Actual zero-net-vector weapons (again, lasers are this by definition) are possible, and while most are BASED on rocket technology or some variation thereupon, they have to be carefully engineered to eliminate ANY transference of force to the weapon itself. I still need to look up the SA rocket launcher from the BBB and check, but if you were attempting unguided shots with the thing, I know I would impose a penalty with the thing. Not a big one, mind you, but enough to honor the dificulty of firing off two rockets in three seconds. Since guided weapons use diferent mechanics and don't care about initial aim point, then it's irrelevant.

I've fired a single shot rocket launcher before and it is sorta recoilless (it rumbles around but there is not discernible forward or backward kick). My question would be how do you have a SA rocket launcher in such a way you can load it quickly enough to be SA and still keep the rockets from igniting each other?

BTY I can't find a SA man portable rocket or missle launcher in the BBB. Can you reference a page number please.

It's the Mitsubishi Yakusoku MRL on p. 319/320 of SR4A or p. 310 of SR4.

The Soviets developed a light weight auto-mortar in the mid-twentieth century. It was clip loaded and fired very fast. But an even simpler sollution would be a revolver magazine. We've seen that on tanks for years, and without the full recoil forces associated with a high-pressure tank gun, you could spin a new round into position much faster. Fast enough that you could achieve an aimed shot every second and a half to get to SA rate of fire, per RAW. I still say there would be enough recoil in such a system to require a small recoil modifier.

I agree with you totally. There should be some small recoil modifier.

BTW can you stop using a green colour on your posts. It give me a headache.

Well, I went and played with it and settles on a slightly different shade. Hope this works better. (I am editing all my old posts for consistency and ... to be polite)

I'm curious as to why people think that they need to mess with the font style for every post.