I don't believe that any semi or full auto launchers stated anywhere.

My guardsman has recently become fond of using a grenade launcher. He has also come to the conclusion that being able to launch several grenades in one burst would be advantageous. He likes to be thorough. His Tech Priest agrees that that amount of firepower is a wonderful idea and is perfectly willing to make the modifications.

How would you handle a semi or full auto launcher?

Buy a Boltgun - they're semi-auto mini-RPG launchers.

I have a bolt gun. I love my Bolt Gun. My Bolt Gun Loves me. Every now and then I need to wreck something really big or waste a crowd really fast.

Bolt guns don't have a Blast Radius.

A blast radius is a very fun thing.

So would you roll scatter for each grenade or roll scatter for one and then add a modifier based on degrees of success or failure or number of rounds launched?

take your grenade launcher that has a drum of 6 grenades then the add a barrel for each of the drumed grenades, and the trigger, so it ends like.

Range 40m
RoF s/3/6
Clip 6
Rld 2 Full
Special As grenade and Inaccurate and Massive Recoil*
Weight 19 kg

Cost 500 original+rebuild cost 1000.

Massive Recoil: Due to the massive recoil firing the weapon on semi and full auto, it causses 1d5 I primitiv the grenadier's arm for semi auto and 1d10 I primitiv to the arm for full auto.

Now even necrons get scared when its loaded with 6 krak grenade and pointed at them.

Roll to hit as if you were firing a single shot for the first grenade then either have the remaining grenades scatter d5 meters from the impact of the first or have each grenade scatter from the previous one, like a chain of doom.

I think you could have a semi auto grenade launcher as a basic weapon but I'd probably only let a fully automatic one as heavy weapon.

Imagine that on overwatch. Surprise!

Face Eater said:

i like that idea of that

This is the sort of weapon that I'd love to use as a "GM-decides the effect". Autofiring crakgrenades is one thing, that will just be like a very nasty heavy weapon. Autofiring fraggrenades against a horde of heretic industrialworkers that feels the emperor is giving them too low a salary, that's more of a storytelling moment involving a lot of adjectives, and very few dicerolls.

This could get pretty exploitable game-mechanic-wise and it also ends up being a bit un-realistic, expensive, and/or, at the very least, tactically redundant. In reality and in-game, if one grenade doesn't do what you need, then I think it may be time to switch to a different type of grenade. If there is no grenade that will do what you want, then I believe it has become the time to upgrade to a man-portable missile launcher. If you need multiple missiles to decimate that moving target, then it's time to hop in a tank or similarly-geared assault vehicle and get to work.

Why use one when you can use 3 or 6?

You can also think of it as crowd control with a vengeance.

My guardsman dosen't understand the meaning of the word subtle, or that it even exists. There is the application of force and then there is wining.

And don't worry, he has a command Rhino that he hijacked from the local Arbities.

ItsUncertainWho said:

that sounds like what my guardsman would do 'cept he went and swiped a Russ from a PDF motor pool and went for a joy ride, and tehn got thrown in jail for 20 yrs. lol

A full auto would have to be a heavy weapon. That would also require it to be vehicle mounted or tripod. So if portable you are looking at some set up time. Grenade launchers on any type of rapid fire are not that accurate especially once you factor in the recoil.

You could use a variation of the Thud Gun templates for where they land. It would probably require mapping out the encounter. But basically roll the first hit location, have round template for the burst with the numbers 1-10 spaced around it. Roll a dice and the second round lands in that direction by a random distance, rinse and repeat for the number rounds fired. This also may cause some pause on the players part from firing them at close range as the randomness could make the rounds back onto them.

If a player complains that it's to inaccurate and they want to place four round on the same target just remind them it's a support weapon designed for area suppression. Reload on such a weapon would probably be 2 full rounds.

I'd also go with the "semi auto for big handeld revolver GL, full auto for heavy weapon on tripod" sentiment. Closer to real life and less Schwartsnegger.

I would not give bonus for firing several shots though, the devation rules for missed grenades is good enough. A automatic GL pretty much autokills everyone inside a small area, unless they were flak armor or better (5 protection vs exposive). Krak grenades is another matter, which basically makes it an expensive and slightly better heavy bolter.

Sarius said:

Would a normal person even be able to stand up to the recoil of a gun that fires projectiles witha caliber of 40 millimeter in rapid succession without any form of bracing first?

I mean, not even bolter rounds (well the human used version anyway) has a 40 millimeter caliber (they usually have the grossly large 0.75 caliber which means that it is 0.75 parts of an inch. An inch being roughly 25 mm, making a bolter round about 18.75 mm caliber). And a bolter recoil is described as kicking pretty hard on semi- and auto-fire in spite of the weapon's heavy weight absorbing much of the recoil (explaining why bolters look quite large and heavy). A weapon that fire's 40 mm rounds on auto-fire would have to use a lot more explosive propellant than a single bolter-shell, meaning a lot heavier recoil. Sure, for firing one shot it's feasible, but several shots in rapid succession?

Let's put it like this, would you like to try firing a .50 cal machinegun (found usually as pintle mounted weapons on tanks) from your hip without any bracing at all? I know I wouldn't (I prefer my arms attached to my sockets). And a .50 cal (half an inch caliber) would still be small potatoes in comparison with something as big as 40 millimeter.

So a rapid firing 40 millimete grenade launcher attached to a tank seems realistic. But as a portable weapon that doesn't need to be braced? Maybe if you're a Mechanicus Secutor equipped with a Manipulator Mechadendrite and use the mechadendrite to brace the gun first. But for a normal human being? Sounds outright dangerous to me.

(then again, im assuming that the grenades fired from grenade launchers in 40K are the 40 mm kind. Based on the GL's ive seen carried by Imperial Guard miniatures and they look pretty much the part).

If it were a rocket/missile launcher on the other hand it would be a different story (since missile launchers are usually pretty much recoil-less). Which would also serve to explain the hybrid ammunition that bolters use (if the shell had to be propelled by an explosive propellant alone, I think the recoil would've been arm rippingly nasty).

Actually, a company in South Africa already makes a man portable automatic grenade launcher for the 40x46mm grenades (the Y2 MGL). It's rated at 120 rounds/sec and doesn't rip people's arms off. 'Course, it's a shorter range than the 40x53mm ones, because it's only shooting them at ~250 ft/sec rather than 1000-something, but that's actually closer to the launcher in Dark Heresy anyway, since the 40x53mm generally shoots out to over 1500 meters with pinpoint accuracy, and almost 2000 if don't mind missing a bit.

As far as how to model an automatic launcher, if I were running it I'd say to shoot and scatter (or not) as normal, and then scatter every round fired 1d5 meters from that point based on the scatter chart.

Example: Guardsman Grakk fires the launcher on semi-auto (3 frag grenades). He rolls to hit and misses, and so scatters the target point 1d5 meters. He rolls 8 for distance, and a 3 for direction, so he moves the target point 4 meters past and to the right of where he wanted. He then scatters each of the three grenades from that point as normal.

If that proves to take up too much play time, I'd say increase the blast radius of the grenade fired for every three grenades fired and add tearing.

Tyraxus said:

Who says that gun nuts do not think practically !

Tyraxus said:

Using less explosive propellant is always a solution (explaining the shorter range). I was thinking in the way of auto-fire with the 40x53 mm's and if you're going to lob those out at 1,5 kilometers on full auto then the recoil would be nasty.

Yeah, autofiring 40x53s wouldn't be possibly without some kind of heavy bracing (say mounted on a truck), seeing as you need to brace the standard launchers for the 40x53 before firing on single shot.

Strikes me that there is also room for a heavyier grenade launcher to then, perhaps with only a few types of grenades.

For balance sake I'd still probably limit a basic weapon to semi-auto though.

The Autocannon is a Full-Auto capable weapon firing explosive rounds, but no Blast radius.

As of current weaponry, the MM1 can fire 30 grenades a minute, which would translate into a RoF of S/2/- or something. I'd expect it to be improved upon in 38 000 years It doesn't have that much of a recoil either.

And the MGL Mk1 fires 6 shots in less than 3 seconds. That would be a RoF of S/3/6, ya? Weighing in at 6Kg empty, it's a blast

That's an impresive gun alright but it's still only semi-automatic. Just a good enough semi automatic to fire all it's rounds within 3 seconds. I'm sure most semi-auto pistols and shotguns can beat that (though that's probably as fast as physically possible to pull a trigger).

Having said that cranking of the trigger of a semi auto pistol as fast as you can is just going spray bullets in a general ark and doing that with a grenade launcher is a win regardless of accuaracy.

But i digress i wasn't saying that that they couldn't be done just that for game balance it shouldn't be available. I'd say the user needed at least bulging biceps before he uses suspressive fire with frag grenades (no I don't care if i technically roll a hit or not) or short range automatic burst of krak grenades.