So, I noticed that while there have been several threads in the past about Las-weapons in general, none of them seem to have ever actually been here in the House Rules sub forum. I figured I would share my own thoughts on the topic, and place them here. If anyone decides to use what I put here, I strongly recommend applying the proposed modifications equally across the board to Rogue Trader and Deathwatch as well.

That said, here goes.

Proposed Las-Weapon House Rules
"Batteries" Included

1. Penetration ¹ : Increase all las-weapons with a published Penetration of less than 5 by 1 .
2. Hot-shot Charge Packs: A las-weapon equipped with a Hot-shot Charge Pack sees its Damage increased by 1 , its Penetration increased by 3 , and it gains the Tearing ² Quality. Whilst so equipped, a las-weapon loses its Reliable quality and sees its Clip reduced to 1 .
   Hot-shot Charge Packs may be used with any Basic or Pistol las-weapon with the following exceptions: Hellguns , Hellpistols, and Duelling Las * .
3. Overcharge Packs: A las-weapon equipped with an Overcharge Pack sees both its Damage and Penetration increased by 1 , while its normal Clip capacity is reduced by half (round up if necessary).
   Overharge Packs may be used with any Basic or Pistol las-weapon with the following exceptions: Hellguns , Hellpistols, and Duelling Las *.
4. Hellguns and Hellpistols ³ : Voss-pattern Hellguns and Hellpistols gain the Gyro-Stabilized Quality found on page 143 of the Deathwatch corebook.

¹ Dueling Las*: Both the Belasco in Rogue Trader and the Khayyer-Adden in the Inquisitor's Handbook are basically Laspistols of fine manufacture using Hot-shot Charge Packs and their profiles remain mostly unchanged.
² Tearing : The Belasco Dueling las adds the Tearing Quality to its profile. This brings it more in line with the idea of it using the equivalent of a Hot-shot Charge Pack and makes it more comparable to the Khayer-Addin Dueling las.
³ Hellguns and Hellpistols : All Hellguns and Hellpsitols may use standard charge packs in lieu of their more common backpack capacitors. The Cadian, Lucius and Voss patterns consume the energy from the Charge Packs at four times the rate of their common lasgun and laspisol counterparts. This gives these Hellguns a Clip of 15, while their Hellpistols counterparts have a Clip of 8 (30/4; 7.5, round up to 8). The D'Laku continues to receives 12 shots from a standard Charge Pack, per its description on page 133 of the Inquisitor's Handbook .

Some might think this makes Lasweapons too powerful. Let me address some points and explain my thoughts.

Penetration:

1. I feel an increase to Penetration is justifiable. After all, a weapon-grade laser should be able to burn through a leather jacket. As it stands in the RAW, even Gang Leathers in the corebook counted their 1 armor against a lasweapon ( Primitive - half AP, rounded up is still 1).
2. This increase should also makes the ubiquitous "Guardsman's Friend" lasrifle a touch more comparable to the so-called "God of Small Arms and Autofure" autogun.
3. The limiting of which lasweapons are effected by this rule prevents Penetration 8 Hell-weapons or Penetration 11 Lascannons. It brings the older Voss and D'Laku patterns, a little bit more in-line with the more recently published materials.

Hot-Shot Packs:

1. I felt that the benefits of a using Hot-Shot Charge Pack were not quite equal to the penalties, but I also didn't want to make them too powerful. In the case of these rules modification, most lasweapons using a Hot-shot Charge Pack will still perform within the scope of the RAW; that is to say Penetration comes out to 4, +1 Damage , gains Tearing , loses Reliable , and only one shot. It does give the Long Las a slightly better Penetration ; base Penetration of the Long Las becomes 2, and the Hot-shot Charge Pack will increase it to 5 with this rules.
2. I really feel that weapons such as the Belasco Dueling las should conform to a standard; in this case the Khayer-Addin and their common feature of single shot Charge Packs. Therefore, Tearing should be added to indicate a form of Hot-shot Charge Pack .

Overcharge Packs:

1. The modified rules for the Overcharge pack makes their benefit comparable to the Expander Rounds available to many SP weapons, which do not see a reduction in their Clip when using said rounds.

Hellguns and Hellpistols

1. Standardized the ability of all Hellweapons to substitute standard Charge Packs for their Backpack Capacitors / Ammo Supplies . Seemed reasonable since the socket would likely conform to a Munitorum standard.
2. Giving the Gyro-Stabilized Quality is on a bit of a whim, inspired by the written description of the Voss- pattern guns on page 172 of the Inquisitor's Handbook . This seems an valid addition to further make the Voss -patterns appealing once more. I don't

Anyway, there they are, my House Rules for Lasweapons. Opinions?

-=Brother Praetus=-

I like it, this isn't so complex that there are any rules to remember and it works.

Seconded, although the main "problem" with Las is the lack and overpoweredness of Full-Auto. Since I already boost SA burst the difference is not that great.

For example you'd think a laser shot would burn through a leather armor, sure but so would a revolver shot.

But the best part of these house rules is that they are simple and won't make Lasweapons "required." It is worth to note though that the Long Las w/overcharge packs will outperform the Hunting Rifle (aka sniper) with Manstopper rounds in every way. Except perhaps the annoyingly revealing ray of light that says "I'm here!"

Remember that Pen 2 Dam +1 is better than Manstoppers Pen 3. I don't mind too much as I think SP weapons have awesome versatility to compensate, as well as cheap autofire guns.

Indeed another thread, I'm one of the peeps that started one in the main forum. Mainly cause I posted my post in the form of a question about comparison between SP and LAS. Anyway, for what its worth, if this is THE thread in the houserule section, here is the summary of 5 pages of replies on how to balance las vs SP:

Summary of replies

In all I think the 'charm' of the SP are the SA and FA, this is their area. You *can* have Las with SA and FA but they're just a lot more expensive and rightly so because of the immense power drain you have to do with every shot. So I would argue that Las shouldn't get any (extra) bursts. This leaves either:

1. balancing SP
2. improving damage of Las.

1. I believe there has been one suggestion to balance SP, which sounds attractive:

Remove the +20 BS on FA but increasing SA by +1 hit/DoS

2. There have been a LOT suggestions to improve Las or the use of it:

* Add pen, e.g. 1 on pistols, 2 on basic and 3 on heavy (or double these numbers)
* Add damage, e.g. dito pen.
* Half T (rounded up) vs E (and X)
* Allow modifications (depending on quality of weapon): common +1 dam, 2 charges; good +2 dam, 4 charges; best +3 dam 8 charges
* extreme range = long range
* shift the range penalties by 1 step in favor of Las (because of its ease of use and high accuracy)
* allow free (half) aim action after first shot (because EVERY las shot is effectively a tracer round so you can adjust your weapon)

There have also been given quite some reasons why Las (circumstance wise) is better then SP:

* there are circumstances that Ammo IS an issue
* charge packs can recharge (SP obvisouly not)> Net 1 hour; In Bright Sunlight 8 hours; Overcast 12 hours.
* untraceable
* highly accurate
* easy to use/learn to use
* shooting with las into (so not from within) water is not a problem (although your angle might be slightly off due to the refractive index of air-water), with an SP it is. (The latter is confirmed by Mythbusters)
* its less pollutant (which really matters if you live in a Hive)

Friend of the Dork said:

Yes, Pen 2 with a +1 Damage might appear better than Manstoppers Pen 3, but an autopistol (Clip 18) with manstoppers is still clip 18. Another point I mentioned are the Expander Rounds in Rogue Trader on page 136. They are both +1 Pen and Damage. My house rule merely makes the Overcharge Pack comparable to Expander Rounds, while still seeing the number of shots reduced to half. Also, while that will typically bring the number of shots to 30 for the lasgun; comparable to the autogun, the lasgun cannot be fitted with a Shot Selector, and therefore still lacks a certain versatility attributed to the autogun, not to mention a distinct lack of autofire in almost all models of las weapons.

The lasgun has been described as using a "standard 19 megathule (megajoule?) charge pack." Someone in a thread on another forum once pointed out that a 7.62NATO transfers ~3.5 kilojoules of kinetic energy to its target. So, a lasgun netting 60 shots, presuming 100% efficiency, would hit with approximately 316 kilojoules of energy. This is also presuming no degradation of the beam from emitter to target. Now, I am no physicist by any means, but I'm fairly certain a safe bet would be that only 25-50% of said energy actually reached its target due to transfer loss in the weapon, and atmospheric refraction. So, figure an average closer to ~79 kilojoules of energy striking the target. So, yeah, sorry, but ultimately, I think a lasweapon should be a little more destructive shot for shot to comparable projectile weapons.

Megajoule

The megajoule (MJ) is equal to one million joules, or approximately the kinetic energy of a one-tonne vehicle moving at 160 km/h (100 mph).

wolph42 said:

I'm not looking to rewrite or rework any additional mechanics within the system, and honestly feel the rules for SA and FA are fine. Part of the whole purpose of a fully-automatic weapon is to quickly put more rounds down field to better increase one's chance of hitting a target; hence the reason I'm fine with the bonuses to BS tests. With the more modern automatic weapons, we see the implementation of barrel compensators/muzzle breaks which significantly reduce recoil and allow for increased accuracy when firing multiple rounds quickly.

The

Anyway, we've all got different views on how best to compensate within the system things we feel are either inaccurate or overpowered. Thanks for the feedback and all.

-=Brother Praetus=-

@ Brother Praetus: Yeah I don't think it's too bad, just slightly better in terms of damage/penetration. An Autogun still has decent ammo capacity, and together with boosted SA and/or nerfed FA, they become the better option. Not by far, and ppl can still choose SP weapons for artistic reasons, but slightly better until the acolytes earns more money.

As for your MJ theory I don't buy it, Lasguns in DH is not realistic and is not meant to be anything like the super deadly weapons of for instance, Dune.

They are called "flashlights" for a reason in 40k and they are not based on kinetic damage Not if you want a weapon that fits more your description then Plasma fits that alot better.

Also RT weapons etc. may fit in that game but they are not part of DH so anything used from it is basically optional rules at best. To these so called expanding bullets are completely unrealistic because of the increased penetration. Dum-Dums are expanding in their own rights, and fits the RL equivalent rather well. In other words: I wouldn't call lasguns in DH overpowered if I used special las rules from Deathwatch for example. Not that they exist, but I hope you get my point.

Sorry for ressing the thread if it bothers anyone, but i had an idea yesterday:

DMG Ammo pack, Adds +3 dmg but doubles armour (like DumDum bullets for the SP weapons) reduces Clip by ½

Penetration ammo pack, +4pen but lower dmg by 1, reduces Clip by ½

My thoughts would be that neither of these are compatible with Hellguns or Heavy classes las weapons.

Might wanna spell out gyro-stabilizied trait for those that play DH and have no interest in buying DW.

My solution has been pretty straightforward, and has roots in both the earlier edition game rules as well as the 40k universe fiction. In particular, almost all lasguns (exception being Longlas and other specialist/civilian kit) have full auto, guardsmen switching over to this fire mode with shocking regularity in more novels than I care to recount here. Second, earlier editions of 40K (and Necromunda) all have Lasguns sporting a respectable armour penetration rating. Both Lasguns and Boltguns of that time had a -1 AP, enough to completely IGNORE Flak and reduced the effectiveness of everything else slightly. Lasguns have since lost their AP ability somehow with the change in tabletop armour rules, Flak was improved to 5+ save and the Boltgun was set to AP5 to continue ignoring it. Therefore:

All non-specialist Lasguns gain 1 extra penetration to their profile (should have probably set it to 2, but it has been going ok so far) and gain a Full-Auto fire mode equal to twice their burst-fire rate (in most cases 6).

Thus:

Mark III Lasgun 100m 1D10+3 E S/3/6 AP1 Clip:60 R:full Reliable The most common Lasgun in the galaxy!

Kantrael Pattern Lasgun 100m 1D10+3 E S/3/6 AP1 Clip:60 R:full Reliable, Bayonet-mount Cadian model Lasgun.

And so on....

Not overpowering, but it at least makes the poor Lasgun a viable weapon choice. Hotshots and Overcharge packs can further modify these, naturally.

While I am at it, the Hellgun stats in Ascention are just plain WRONG in regards to range. TT Lasgun 24" = DH 100m, so therefore a TT Hellgun 18" =/= 50m, it should be 75m! Pattern is likewise WRONG! Note that Cadia is not a Forgeworld.

Kantrael Pattern Hellgun 75m S/3/- 1D10+4 E AP7 Clip:40(beltpack)/150(backpack) R:2full Targeter (may mount aditional sight)

The Lucius Pattern Hellgun in RT has a range of 110m and lacks the integral targeter. Pretty much the same otherwise.

While las-weapons have a f-load of energy they have zero momentum. All that energy is transfered to the first thing it touches, skin, leather jacket, the leaves of the bush your hiding behind (No it would appear that GW did not think of that in regards to the Jungle Fighters). This would typically cause the thing hit to explode (Flak board exploding in the novels due to las hits would seem right). Now a piece of flak armour exploding 1/2" from your skin will hurt, but not as much as your skin exploding.

Before someone starts on the Las-Cannon, I would guess that it's ability to kill tanks (Excluding cool fluff reasons) would come from something akin to that amount of armour exploding/ melting/ warping (As metal tend to do under that kind of heat) having consquences on the rest of the tank.

For a las-weapon to cut through something, penetrate something would require a constant beam.

Shockwave said:

That's not really accurate. The laser is not going to deliver all the energy instantly to the first thing it touches. In fact, all lasers have some wavetrain length which determines how "long" the laser pulse is. However, that is secondary to the actual point that I want to make. What happens when a laser strikes a target is that it delivers energy to the target in a concentrated fashion, such that it vaporizes whatever it touches. The leaf in question would not explode, it would simply have a hole burned through it, a rather tiny hole in fact. The amount of energy needed to vaporize the cross-section of that leaf would indeed be lost from the final impact, very similarly to how a bullet loses energy as it passes through objects (armor, leaves, whatever).

In short, lasers do damage by vaporizing their targets not by "exploding" them. With a lascannon you're basically putting a hole all the way through the tank and if a lascannon works like I want it to (rather long time length laser pulse) then you can move the lascannon slightly and "slice" the tank. (I'm drooling at the thought.) The laser delivers so much energy that it simply vaporizes the metal, as opposed to melting it.

As a technical point light does have momentum. So, a laser will carry some momentum with it. Again, this isn't overly relevant to the situation at hand.

To demonstrate this and to make you very very happy, I present to you a real-life laser gun.

That's interesting, most of what I said I believe i (Loosely) paraphrased from a writer on the Btech forums who i believe has a physics background, and is the go to person for such things.

{EDIT}

Lasers in most fantasy/ sci fi setting have a tendency not to slice, (Bab5 being the only one coming to mind) they tend to bolt's, which tend apparantly change the effects/ energy requirements or some such.

Flail-Bot said:

What do you think happens to the material after it is vaporised ?

It expands. If you have put enough energy into it (like 40k lasers do and the laser in your video doesn't), it expands violently. Which is the explosion.

Have a look at this page at Atomic Rocket for more details on how a laser weapon would work.

I also have a physics background.

Now, you're right that things that are vaporized have a significantly decreased density than solids. However, the total volume vaporized by a laser weapon is probably going to be pretty small. Your consideration is duly noted, however, and is an interesting proposal.

We should probably test the effect. I'm thinking that one may actually desire a "longish" pulse of laser for a las weapon because it will give the vaporized material some time to escape. Perhaps a double pulse system would work well...

Just to provide some input from the Munitorum Manual:

"It fires an explosive energy blast with a similar effect to a bullet or small shell."

As for the topic at hand: My opinion has always been that Overcharge Packs as a dedicated magazine were a mistake. The las weapon is obviously capable of enduring shots of higher energy, else you'd need more than just switching power packs. All the pack does seems to be feeding the lasgun with a greater amount of energy whilst keeping its storage capacity identical. So why not integrate the ability to switch from low to high powered shots in the rifle instead of making it depend on the magazine? Like it has been done for military-grade plasma pistols? And how the lasgun is described in the Uplifting Primer, the Munitorum Manual or the computer games (and likely a lot of novels as well)? After all, lasgun "shots" cannot be measured and counted in unalterable shells - following common sense, they are flexible amounts of energy that can be as great or as small as the user wants and the weapon is capable of handling.

In my opinion, the most obvious advantage of the lasgun is not its damage but its versatility. Making Overcharge not a magazine but an integrated feature of at least some las weapons would greatly affect their attractivity. Just a thought, of course.

As a modification to OP's suggestion regarding Overcharge Packs I would thus propose the following settings:

• Min: Damage and Penetration as per RAW
• Med: +1 Damage, every shot counts as -2 ammo
• Max: +1 Damage and +1 Pen, every shot counts as -3 ammo

or alternatively:

• Min: -1 Damage and -1 Pen, on a dice roll of 50 or lower the attack does not consume any ammunition*
• Med: Damage and Penetration as per RAW
• Max: +1 Damage and +1 Pen, every shot counts as -2 ammo

*: I realize this is a bit wonky but I don't think people want to keep track of "half shots". There are alternatives to this, of course, such as having single shots still consume a full round of ammunition but applying the "discount" to semi- and full auto bursts.

New Black Crusade has Variable setting. This allows the weapon to fire on Overcharge for +1 or 2 damage for 2 shots worth of ammo, then Overload for +2 Damage & +2 pen for 4 shots worth of ammo. However the Overload mode the Lasgun gains Unreliable & loses Reliable.