Laser rifles in the military

[Pyromancer]

The campaign background I am working on is rather low tech, mostly around TL10 and TL11, and I'm thinking about the military.

Laser rifles are possible at that TL, but how would they be used? They have 100 shots with a heavy battery backpack. If that backpack is 10 kg, it boils down to 100 g a shot.
A 30-round magazines for an assault rifle weighs around 500 g, or 16 g a shot. So if a normal infantry soldier with an assault rifle and 4 mags switches over to a laser rifle, it adds around 8 kg to his load. That's just not feasible. Battle dresses and powered exoskeletons aren't available, yet.

So, how are laser rifles used? And how do tactics change because of them?

 

[Jame Rowe]

I would figure that a laser battery would be getting smaller and/or more power-efficient at TL 10 and then again at TL 11. So both lighter and more shots.

 

[Pyromancer]

I would figure that a laser battery would be getting smaller and/or more power-efficient at TL 10 and then again at TL 11. So both lighter and more shots.

Might be, but that's not what I want to talk about, because it's trivial.

I want to talk about laser rifles with heavy battery backpacks.

 

[Galadrion]

For that tech level, a laser rifle would fit in the same niche as a crew-served weapon, such as a GPMG. It's really too bulky/heavy to fill an infantry weapon slot, although it could be used in a man- or squad-portable role, but it's about the right weight and power for (as an example) a vehicle-mounted crew-served weapon... and the vehicle can also provide the weapon's power needs, eliminating another area of concern. (I'd probably still include the battery pack, to allow for weapon fire in a situation when the vehicle isn't powered up such as an EMCON operation or if the vehicle temporarily loses power during combat.) So at this level, use it as a support weapon. In another one to three tech levels, miniaturization will have brought the weight and bulk down some, perhaps to the point that it can become a true infantry weapon rather than one for the mechanized infantry.

 

[AnotherDilbert]

A big, heavy, single-shot weapon with good range, no muzzle flash, no sound. Sounds like a sniper weapon?

If we assume that the enemy has at least cloth armour so say Armour 8 - 10, most slug-throwers will do relatively little damage. We might need the lasers to hurt the enemy.

 

[Condottiere]

You have thirty kilogrammes of gear your superiors expect you to schlep along, compared to thirty kilogrammes you think are most useful.

I don't know if anyone ever really wargamed out various combinations of gears and military doctrines for the Traveller universe, but the chances are that if you knew the enemy was relying on laser weapons, you'd have the body armour layered with reflec.

 

[collins355]

I suspect laser rifles would mainly be used in zero-G or low-G situations. They have clear advantages in that scenario. Lack of recoil being one. And their mass is less of an issue.

So, mainly for Star Mercs and Star Marines.

And in response, opponents would be using a lot of Ablat/Reflec.

 

[Pyromancer]

Ok, for ground based military: There are lasers on vehicles. I envision a HUMVEE with electric propulsion, a big generator, and a buffer battery, so that it doesn't have to carry ammo for the "MG". It probably can't go full speed AND fire full auto at the same time for a long period. Even if the enemy adds reflec, that's not 100% protection, and it's something they have to carry.
Apart from that, snipers are the only ones who carry laser rifles, but those only have a hand full of shots.

To counter that, smoke that absorbs the laser wavelength is added to the arsenal. Nothing else changes. Tanks don't switch to lasers, but use railguns instead.

 

[Reynard]

"Laser rifles are possible at that TL, but how would they be used? They have 100 shots with a heavy battery backpack. If that backpack is 10 kg, it boils down to 100 g a shot."

I'm using Traveller Core Book 2e and Central Supply Catalogue 1e for references. First, a TL 9 laser carbine has a 3 kg power pack with 50 shots. A TL 11 Advances Laser Rifle power pack is 2 kg and holds 100 shots. Except for the Autopistol magazines, there's no mention for magazine(loaded weight) possibly because of the wide load capacities ranging from 4 shot to 100 for the RF light ACR. The 2-30 round Autopistol magazine could be an indicator at 500gs and the 45 round AP snail drum at 750gs figuring around 17gs per shell so a 100 round RF lt. ACR magazine would be 1.7kg. Still sounds good for weight compared to a 100 shot power pack EXCEPT the power pack is rechargeable. That means no supply vehicles carrying literally tons of spare clips.

Another advantage to laser weapons is silence. No scifi ZOWIE sounds on the battlefield. You can't easily trace the source back. Next is the damage, laser carbines start higher than most slug thrower longarms and the damage goes up with each TL advancement.

As we see today sometimes quantity of cheaper, less powerful weapons can win battles but the advantages from more powerful weapons in the hands of a force willing to pay the price often turns the tide.

Oh as to reflect and ablate, ablate goes away as it take damage and lasers have lots of shots while reflect as the book says aren't always available and are not total proof against lasers.

 

[Pyromancer]

"Laser rifles are possible at that TL, but how would they be used? They have 100 shots with a heavy battery backpack. If that backpack is 10 kg, it boils down to 100 g a shot."

I'm using Traveller Core Book 2e and Central Supply Catalogue 1e for references.

My reference is the German 1e, and there, the laser rifle is "powered by a heavy backpack".

Still sounds good for weight compared to a 100 shot power pack EXCEPT the power pack is rechargeable.

The ability to recharge is great from a high level logistics standpoint, sure. But in the field, you can't just return to base, plug in your laser and wait a few hours for it to recharge after you have fired your 50 or 100 shots. You need to reload NOW and continue firing at the enemy. That means you need big, heavy spare batteries.

Another advantage to laser weapons is silence. No scifi ZOWIE sounds on the battlefield. You can't easily trace the source back.

Laser fire won't be quiet, but since the sound will mostly come from the ionized path filling with air, the firer will be harder to spot.

 

[phavoc]

They would most likely be squad-support weapons. The issue of ammunition (i.e. recharges or new backpacks) is immaterial to the discussion. Why? Because all weapons require ammunition of somesort. You need to assume that a logistics tail is present and can provide ammunition and supplies to your troops on the front line.

More than likely I would say that the assumption is the fire-team equipped with a laser rifle is going to be resupplied with replacement packs while the depleted packs are taken to the rear and plugged in to recharge. It would be safe to assume that for each Laser Rifle you would have at least 3 additional packs in the supply train. That's just a guestimate, but until Dunnigan writes an updated version of How To Make War (52nd century edition), all you have is guestimates.

 

[Condottiere]

If you understand the constraints of the conditions both sides were operating under, whether budget, geography etcetera, you have a pretty good idea what's workable.

Canon says gauss rifles are standard at technological level thirteen, and statistically speaking, Advanced Combat Rifles don't appear too bad.

 

[Jame Rowe]

I would figure that a laser battery would be getting smaller and/or more power-efficient at TL 10 and then again at TL 11. So both lighter and more shots.

Might be, but that's not what I want to talk about, because it's trivial.

I want to talk about laser rifles with heavy battery backpacks.

It aint trivial to me, but I am one of those who likes thinking about the implications of tech advancing.

 

[Ishmael]

imtu, I use laser rifles as target designators for guided sniper munitions. The guided sniper munitions might be SEFOP round scaled for anti-personnel fired from a remote mortar. Or it might be a guided kinetic round from a more conventional sniper rifle fired from a different location.

 

[steve98052]

Another advantage to laser weapons is silence. No scifi ZOWIE sounds on the battlefield. You can't easily trace the source back.

Laser fire won't be quiet, but since the sound will mostly come from the ionized path filling with air, the firer will be harder to spot.

In an atmosphere, the ionized path would be a glowing blue line from source to target, with a loud noise that radiates in a cylinder from the entire line. The loudness would depend on the degree of ionization that results from atmospheric absorption of the laser beam, which would depend on weather and the color of the laser energy (which might be tunable for some weapons).

An ordinary supersonic bullet produces two noises: a blast that radiates spherically from the muzzle of the weapon, and a sonic boom that radiates conically from the supersonic portion of the bullet's path. The loudness depends on little other than the planet's atmospheric pressure and the power of the cartridge.

A soldier accustomed only to slug weapons would have a hard time locating a laser shot by sound, particularly if the color is tuned to minimize atmospheric absorption. But a soldier who has trained for the presence of laser weapons on the battlefield would have some idea of how to locate lasers by sound.

 

[phavoc]

Using a laser on the modern battlefield is like waving a flag showing where you are. Passive laser detection systems would easily pinpoint the location of the lasing device.

For slugs you'd need at least two audio detection devices to give you a good idea of where someone is shooting at your from. If you had three well placed ones you could triangulate the firing position pretty much upon detection.

Virtually all offensive weapons have a passive method of tracking back the original firing/launching site.

 

[Reynard]

I believe laser sensors, the ones on vehicles to activate smoke and anti-laser aerosols, detect lasers that strike them not some sort of general sighting ability.

"A laser powerful enough to cause physical harm to a target would surely be able to ionize air. And if I recall correctly, heating a gas changes its index of refraction, as evident in the heat lines over highways on a hot day. The difference in the index of refraction of the ionized air and the surrounding air could cause the light to scatter enough to be visible, but the actual beam of light would have to be contained within the column of ionized air. So, yes, you should be able to see these lasers, but they fire in extremely quick pulses, and it takes time for a laser to ionize air,..."

"Currently researched high-energy laser weaponry (the MIRACL laser, the Pulsed Energy Projectile and the Tactical High Energy Lasers) use deuterium fluoride lasers, which operate at the wavelength of 3800 nm. Visible light has wavelength range of 390 to 750 nm.
Even if the laser would use visible light, the beam would only be visible in medium that would partially reflect the light. As for example water particles (clouds, rain, fog) or smoke.
US Navy testing their THEL (note how the beam is not visible):
http://www.youtube.com/watch?v=XyTRhw8qmHE
Also, from usefulness point of view, especially for man portable weapon, you don't want visible beam, as that would put shooter in tactical disadvantage. And indeed, the article you refer to talks about goals:
As a lethal system, a laser sniper rifle would be a formidable weapon: perfect accuracy at any a range measured in miles, with no windage, no drop, and no need to allow for target movement. And it would not give the firer’s position away with a report, smoke or muzzle flash – all the enemy would see would be the effect when it hits the target."

 

[steve98052]

If I were building a laser sniper weapon with a combination of present day computer technology and Traveller laser rifle technology, I'd attach a target designation computer, a powered aiming device, and the laser weapon itself.

To use it, the sniper aims at a target, pulls the designation trigger, and the computer tracks that target (for as long as the target remains if the scope's field of view), but doesn't fire. Then the sniper can aim at another target, designate, and continue until the computer says that the weapon doesn't have enough power to shoot them all. After designating all the targets that fit in the field of view (or the powered aiming device), the sniper pulls the fire button, and the weapon shoots each target in order, as long as targets remain in the field of view. With a high rate of fire, the targets just hear, "boom, boom, boom, boom, boom, boom," from their leaders from the pulsed heat blasts as they're hit, then, "thud, thud, thud, thud, thud, thud," as they collapse from their wounds.

Of course, if the rate of fire is slower (which I would probably rule is the case if I were game-master of a military campaign, to make things more of a challenge), targets after the first would be able to react and take cover, as long as they knew that taking cover was better than trying to spot the sniper and shoot back.

 

[Condottiere]

Two issues that I can think of, is how heavy are the battery packs of the laser smallarms, and how long will it take to charge them.

 

[Jeraa]

I see no reason why a laser can't be directly connected to a vehicles power supply, a base's power grid, or a portable generator. Not just to recharge, but as an actual power source. Might require a different cable, or an adapter. That would make it a viable support weapon with practically unlimited ammunition (as long as the power supply remains intact).

Individual soldiers probably wouldn't be armed primarily with laser weapons. The gauss rifle is cheaper, has a much longer range (really? 600 meters compared to the lasers 200-400 meter range?). The gauss rifle is capable of automatic fire, has armor piercing capabilities, is lighter (which allows more ammunition to be carried, though actual weights don't seem to be mentioned anywhere in Mongoose Traveller 1e or 2e.). It can fire special types of ammunition (gauss weapons are not one of the prohibited types according to CSC 2e page 138).

Gauss rifle damage is less, however. 4D compared to the laser rifles 5D or 5D+3. Though with armor piercing capability, this is somewhat mitigated. Armor piercing is 5 for the base round, which costs Cr0.5/shot. Using actual armor piercing rounds boosts this to AP 9, and brings the cost of 80 rounds to Cr160 (Cr2/shot). Using APDS (Armor piercing discarding sabot) rounds boosts this to AP 17, boosts the range to 660 meters, and costs CR200 per magazine (Cr2.5/shot). TL 16 Directed Plasma rounds (possibly in the design stage, not ready for production in the TL 15 Imperium or at least not widely available) gives the weapon 5D damage and AP 15, at a cost of Cr400/magazine (Cr5/shot).

For reference, the laser power pack holds 10 shots, and costs Cr1500 for the TL 9 laser rifle (Cr15/shot) and Cr3,500 for the TL 11 pack (Cr35/shot).

It seems the only advantage of a laser weapon, at least as far as Mongoose Traveller 2e is concerned, would seem to be the ability to connect to an effectively unlimited power supply of a vehicle or base. And even that isn't actually stated in the rules, but would make sense. At the very least, they do allow for after battle recharging, giving effectively unlimited ammunition over time if not in an individual battle.

Edit: And I just noted this is for a specific setting, TL 10/11, where gauss rifles are TL 12. In that case, much of the same still applies though actual numbers may be different.

The TL 10 advanced combat rifle also has a greater range than the laser (again, really?), is cheaper, and lighter. Ammunition cost is only Cr0.375/round. Autofire capable and can use special rounds. Only deals 3d6 damage, however. APDS rounds give them AP 9, +10% range, and cost Cr1.875 each.

TL 10 combat armor only provides 13 protection. TL 11 laser rifle(5d6+3) deals, on average 20.5 damage. Against the combat armor, that gets reduced to 7.5 on average. The advanced combat rifle with APDS rounds deal 3d6 damage (10.5 on average). With AP 9, the same combat armor only provides 4 protection. Average damage would be 6.5, only a single point below the laser, but with all of the other adavantages the combat rifle brings (greater range, lighter, costs less, more available ammunition, can fire RAM grenades, autofire, etc.). With a Heavy ACR also firing APDS ammo, which is Bulky (requires Strength 9 to fire without penalty, but a Cr500 gyrostabilizer can remove that), you deal 4D damage with an AP of 12. Average damage against the armor would be 14 - effective protection 1 = 13 damage gets through. 5.5 more average damage than the laser, and again all of the other advantages.

Again, the laser seems to lose out unless it has unlimited ammunition. It does over time, but in an individual battle still depends on the Referee.