Assault rifles

[avianmosquito]

Finally, my area of expertise: firearms, more specifically, rifles.

This time around we'll be dealing with assault rifles.

What we need to qualify:
A rifle firing ammunition intermediate between a carbine and a full-powered rifle.
An ORIGINAL idea.
Something automatic or selective-fire is preferable, but not neccesary.
PLEASE CONTRIBUTE AN IDEA. I've seen two on-topic ideas in the first forum, and both of them were branch-offs of mine. Please, give feedback, them give an idea of your own if you have one.

I'll start us off. Since this is such a broad concept, I'll use a family of assault rifles, in this case, the rifle family based off the Terratech T22 Pulse Rifle

Rifle, 5.56mm, T22 Pulse:
Design: Bullpup, blowback shifted pulse
Cartridge: 5.56*45mm NATO, (no shit) 5.45*39mm, 6.8mm Remington SPC
Iron sights: U-notch&shrouded post
Selective fire: 3-round burst, pulse-fire, full automatic
Rate of fire: 1800rpm
Effective range: 650m, (5.56mm) 600m, (5.45mm) 650m (6.8mm)
Length: 85cm
Barrel length: 50cm
Mass: 4kg

The T22PR was introduced as an infantry weapon in 2017, and quickly caught on due to the unique way its recoil behaves. The weapon fires fast enough that it is difficult to distinguish the sounds of the individual shots, and is designed to treat these three rounds as a unit, called a "pulse," which it could fire at a rate of 600/min. Since it fires three rounds so fast, with the weapons blowback shifted pulse mechanism giving a small delay to the recoil, the rounds spread less than a centimetre at 100m. This allows the soldier to effortlessy land 3 rounds on any part of the body they need, making up for the 5.56mm round's dismal stopping power. Greater accuracy can be achieved by getting the weapon chambered in 5.45*39mm, at the expense of loosing a bit of the range and stopping power, and greater stopping power can be achieved with the use of 6.8*43mm Remington SPC, at the expense of accuracy and sheer abundance of ammunition.

The rifle, in 5.56mm and under the designation of M36, fully replaced the M16 and FAMAS in the arsenals of the United States Marine Corps and NATO within a few years. In 6.8mm it became the standard designated marksman rifle of the US ARMY, and in 5.45mm it was quickly adopted by the spetsnaz.

Carbine, 5.56mm, T17 Pulse:
Design: Bullpup, blowback shifted pulse
Cartridge: 5.56*45mm NATO, 5.45*39mm
Iron sights: Aperture&shrouded post
Selective fire: 3-round burst, pulse-fire, full automatic
Rate of fire: 1980rpm
Effective range: 550m, (5.56mm) 500m (5.45mm)
Length: 70cm
Barrel length: 40cm
Mass: 3kg

The T17PC shipped in 219, 2 years after the T22PR, making into standard usage in the USMC designated M6, and a few minor deployments in Germany and Russia, but it was in the end overshadowed by its larger cousin. It was smaller, lighter, had a faster rate of fire. Combine all these things together, and it resulted in a less controllable weapon with a shorter effective range, but this was just fine for a carbine.

Light machine gun, 5.56mm, T215 Pulse
Design: Bullpup, belt-fed blowback shifted pulse
Cartridge: 5.56*45mm NATO, 6.8mm Remington SPC
Iron sights: U-notch&post
Selective fire: 3-round burst, pulse-fire, full automatic
Rate of fire: 2160rpm
Effective range: 600m, (5.56mm) 600m (6.8mm)
Length: 115cm
Barrel length: 70cm
Mass: 7kg

This weapon was produced in significant quantities in 2020, but only saw combat chambered in 5.56mm for the USMC. The 6.8mm version was never adopted by anyone. The T215 had a faster rate of fire than both of the smaller versions, but was still more controllable, if only because it weighed so much. However, it was never meant to be anything more than a base of fire, and that's really all it was good at. It is the least acknoledged of the pulse weapons.

Pulse weapons in general all have three distinct features:

1. An insanely fast rate of fire.
2. An inability to fire rounds in anything but blocks of 3.
3. Pulse-fire. A fire mode that cuts the weapon's rate of fire in half in order to conserve accuracy, but does so in an unusual manner. Instead of slowing the rate the weapon cycles, it fires a 3-round pulse, pauses, then fires another pulse, on and on again. These pauses are brief, taking no more time than the firing of the pulse, but are enough to cut the weapon's rate of fire down to a more controllable rate without giving up the advantages of the extremely rapid bursts.

Fun fact: the slang term for the weapon's extremely rapid 3-round units was derived from the weapon's name, not the other way around. The weapon's name comes from its mechanism, blowback shifted pulse, which uses both a recoil and gas mechanism. It is stated that the greatest advantage of this mechanism is that it gives a slight delay to the recoil, allowing the bullet to leave the barrel before recoil takes effect, a second before it means anything, and a third by the time you notice it.

[Science fiction forum removed from title. ~NL]

[Norade]

Yay, the first bit of anything you've posted that works. Too bad it's just a bog standard slug thrower,

[Samuel]

Why do you need a fast rate of fire for these weapons? Don't basic infantry weapons already put out a large enough volume of fire for their role?

[Dark Hellion]

Yah it works Norade, except all the parts of it that don't.

How does this gun keep from melting the barrel with such an obscene rate of fire? More importantly, why the hell do you need this rate of fire to begin with? How much ammo are you going to need to carry because of this?

Are the weights loaded or unloaded? How mechanically does this blowback pulse mechanism actually work? How does this mechanism actually help against targets hardened against 5.56 rounds?

And now for storytelling elements. What are the distinctive features of the weapon? Any odd quirks or funky gremlins? Who doesn't use these and why? What psychological effect do they have on the nature of warfare?

Really kid, you need to think more and stop expecting people to circle-jerk to your ideas, especially when you display such a haughty attitude.

[Norade]

Yah it works Norade, except all the parts of it that don't.

How does this gun keep from melting the barrel with such an obscene rate of fire? More importantly, why the hell do you need this rate of fire to begin with? How much ammo are you going to need to carry because of this?

Are the weights loaded or unloaded? How mechanically does this blowback pulse mechanism actually work? How does this mechanism actually help against targets hardened against 5.56 rounds?

And now for storytelling elements. What are the distinctive features of the weapon? Any odd quirks or funky gremlins? Who doesn't use these and why? What psychological effect do they have on the nature of warfare?

Really kid, you need to think more and stop expecting people to circle-jerk to your ideas, especially when you display such a haughty attitude.

I'm not a firearms expert, so excuse any stupid seeming statements and questions as I figure out exactly why this weapon won't work.

First, I thought that I had heard of a modern weapon using a 2-round burst in much the same way this weapon does a 3-round burst in that the second round is chambered and fired before the recoil disrupts the aim. If I recall though it would then revert to normal automatic fire after those first two rounds if used in such a way.

Second, would the pause between bursts do anything to help keep the weapon cooled; especially when combined with a cooling system?

Third, I have heard it said that 3-round bursts work well, but more often I have heard it said that they are a poor choice and fire control and regular fully automatic fire is nearly always a better option. Which would you say is more correct?

[avianmosquito]

Why do you need a fast rate of fire for these weapons? Don't basic infantry weapons already put out a large enough volume of fire for their role?

The best method is to keep it on tri-burst. This way you place multiple rounds centre-mass, hitting the lungs, aeorta or even the heart. This single pulse is a guaranteed kill to a human target if placed anywhere on their chest.

As for volume of fire, only fools use full-auto, but fools use it and it only. That's why this is not a standard infantry weapon, it is a marksman's weapon. A marksman will use it intelligently.

[Korto]

OK, I'll bite and post the weapon known to humans as the "Slugga", the signature weapon of the Tai'Qu (ie, the weapon they're most known for, NOT the only weapon they have). I will mention an earlier version of this weapon was posted years ago (it basically got laughed at) when I was trying to work out recoil limits for a practical hand weapon. I'm not military, or even a gun geek, so don't expect much numbers. I'll probably fluff the terminology too.
In human terms the Slugga would translate to a 54mm semi-automatic cannon (or grenade launcher?), firing very low velocity rounds. The type of rounds loaded depends upon the nature of the task; for close assault they normally have shaped charge with a maximum range of approximately 120 meters. They also have shrapnel rounds, EMP, and long-ranged shaped charge and discarding sabot, along with others. The rounds are propelled by chemical propelent. They're basically big, fat, explosive bullets, probably fed in clips although originally I was thinking disintegrating belts.
The weapon is rubber-mounted (for recoil) onto the forearm of their battle armour, positioned so as it can be used as a shield in hand to hand combat (Note - Hand to hand is a viable tactic in this universe, as important as long-ranged fire, due to force field tech I'm spending valuable handwavium on), and specially designed and built for this dual role.
Its maximum rate of fire is approximately 1 round per second, and it is built quite simply and very ruggedly.

I'm considering that it may be the weapon, instead of being dual use gun/shield, with the need for a second (melee) weapon, should be dual use gun/melee weapon, enabling it to be longer, better at long range, etc. I won't take much convincing on this POV, the more I think about it now.

Edit - although that loses being able to swing in melee and shoot at someone else a split-second later

[avianmosquito]

OK, I'll bite and post the weapon known to humans as the "Slugga", the signature weapon of the Tai'Qu (ie, the weapon they're most known for, NOT the only weapon they have). I will mention an earlier version of this weapon was posted years ago (it basically got laughed at) when I was trying to work out recoil limits for a practical hand weapon. I'm not military, or even a gun geek, so don't expect much numbers. I'll probably fluff the terminology too.
In human terms the Slugga would translate to a 54mm semi-automatic cannon (or grenade launcher?), firing very low velocity rounds. The type of rounds loaded depends upon the nature of the task; for close assault they normally have shaped charge with a maximum range of approximately 120 meters. They also have shrapnel rounds, EMP, and long-ranged shaped charge and discarding sabot, along with others. The rounds are propelled by chemical propelent. They're basically big, fat, explosive bullets, probably fed in clips although originally I was thinking disintegrating belts.
The weapon is rubber-mounted (for recoil) onto the forearm of their battle armour, positioned so as it can be used as a shield in hand to hand combat (Note - Hand to hand is a viable tactic in this universe, as important as long-ranged fire, due to force field tech I'm spending valuable handwavium on), and specially designed and built for this dual role.
Its maximum rate of fire is approximately 1 round per second, and it is built quite simply and very ruggedly.

I'm considering that it may be the weapon, instead of being dual use gun/shield, with the need for a second (melee) weapon, should be dual use gun/melee weapon, enabling it to be longer, better at long range, etc. I won't take much convincing on this POV, the more I think about it now.

Edit - although that loses being able to swing in melee and shoot at someone else a split-second later

The weapon to me seems quite a bit over-sized, and would also be likely overpowered. Also, the rate of fire is slow. Thet would need a smaller weapon for more general combat, like a real assault rifle.

[Feil]

Why do you need a fast rate of fire for these weapons? Don't basic infantry weapons already put out a large enough volume of fire for their role?

The best method is to keep it on tri-burst. This way you place multiple rounds centre-mass, hitting the lungs, aeorta or even the heart. This single pulse is a guaranteed kill to a human target if placed anywhere on their chest.

As for volume of fire, only fools use full-auto, but fools use it and it only. That's why this is not a standard infantry weapon, it is a marksman's weapon. A marksman will use it intelligently.

If only fools use full-auto, why not just make the selector only toggle between single and burst, like some modern weapons? Why is a marksman being issued a carbine or LMG? Why is there an LMG that only fools would use at full auto? If the LMG is actually intended to fire fully automatic, why does it have twice to three times the rate of fire of modern LMGs which use the same ammunition? If the rifle is only issued to marksmen, why did you explicitly state that it replaced the M16 and FAMAS? Why can't you ever be consistent?

[Caiaphas]

Okay, great idea, but there are a few problems I'm seeing here. Be forewarned: I sure as hell ain't a gun expert.

If you're firing on full auto, those three-round bursts are going to deplete your ammo pretty damn fast. Besides, that ridiculous rate of fire is going to heat up your barrel fairly quickly, and you're going to get a jam. Boom. Your gun's useless now. My advice: get rid of the full auto. You can pull a trigger fast enough to put a whole lotta lead down if you need to, and the less complicated your gun is, the less likely it'll break. If you've already gotten rid of it, I apologize for the redundancy.

The best method is to keep it on tri-burst. This way you place multiple rounds centre-mass, hitting the lungs, aorta or even the heart. This single pulse is a guaranteed kill to a human target if placed anywhere on their chest.

Only problem with that is that you stated that there's very little spread to those bullets; less than a centimeter at 100m, I believe. If you hit off-center, they're not going to get the vitals, unless one richochets off of a rib, and that's iffy at best.

A light machine gun that fires three times as many rounds per minute sounds and is awesome, but again, you're going to have severe cooling problems, and you're going to need to carry three times as much ammo for the same firing time. LMGs are designed for portability, and lots and lots of heavy ammunition does not lend itself to that. But sure, you may say, you can just carry the same amount of ammo and rely on its higher rate of fire! Unfortunately, accuracy doesn't lend itself well to machine guns. If I'm wrong, by all means, correct me, but the things are supposed to lay out a hailstorm of lead, not a localized thunderbolt. You might adapt this to heavy machine guns, though, provided there's enough ammunition for them; it's going to be a helluva lot easier to solve cooling in a HMG compared to a LMG.

Is your weapon designed for use on unarmored or armored subjects, as in bulletproof vest-wearing versus non-bulletproof? Unarmored, three rounds might be a little overkill. Armored, three rounds might be of more use.

Also, how precisely is recoil solved. If it's by a system of weights and counterweights, give me a M16 any day. Weights just make a gun too heavy and too clumsy.

So, I must ask of you: how do you solve these problems?

[Korto]

The weapon to me seems quite a bit over-sized, and would also be likely overpowered. Also, the rate of fire is slow. Thet would need a smaller weapon for more general combat, like a real assault rifle.

It would be overpowered, except it has to deal with the force fields (not the actual name. I'll think of something better) I mentioned in passing. To defeat them you either have to use something so slow that it passes through, yet still massive enough to do damage OR a very narrowly focused and huge energy spike which can burn out the field as it tries to absorb it. The narrow jet of a shaped charge seems to me to be good for it. The rate of fire is slow as the recoil is still high (it's spitting a big shell), and there's limits to how much 54mm ammunition you can carry anyway. And story-wise, it's an interesting feature of the weapon (hear it in your mind - Boom Boom Boom Boom)

[Covenant]

OK, I'll bite and post the weapon known to humans as the "Slugga"...

Wait wait, stop right there.



Sluggas are the weapons used by the Orks in Warhammer 40,000. They are known for being large semi-automatic weapons that fire large-bore rounds and are generally designed to be used a close-up assault weapons. A rough analog to the bolt-pistol, which fires semiautomatic rocket shells, the slugga is often paired with a choppa for a combination of assault weapon and melee weapon...

Is this accidental? Because, man, I really feel sorry for you if it is. Your Slugga, used by your hulking gorilla-shaped super-durable guys... it really just ends up looking like you've accidentally made up the Orks. Don't take it so bad. I accidentally made up Dr. Who one time, and thought it was very clever, until I realized someone else across the pond had already been doing it for the past eight million years or so.

If it's not accidental, I'd modify the Not-Slugga into something slightly different.

[Ryan Thunder]

EDIT: Goddamnit! I meant to hit "preview"...

[Caiaphas]

Whoops. Hit quote when I meant to hit edit.

[Korto]

Sluggas are the weapons used by the Orks in Warhammer 40,000.

Bugger. They are too. Accidental, named that because originally (in the version that got laughed at, and one of the things they were laughing at) it fired a approx 1 kg slug of lead that, well, slugged you. After the criticism, I decided that there were better uses for such a large calibre.
As I'm aquainted with GW orks (although really fantasy, very little 40k), there's every chance they've influenced my thinking; then again they hardly have a patent on big, hulking, close combat lovers, and mine are smarter!

The weapon may be needing a new human nickname.

[Raxmei]

Wouldn't it be easier to just shoot one large bullet than to shoot three smaller ones? That way you probably come out ahead on ammunition weight and recoil, definitely come out ahead on mechanical complexity, and large calibre bullets aren't bad at killing people.

btw, there's absolutely no need to put the forum name in your thread titles.

[avianmosquito]

Wouldn't it be easier to just shoot one large bullet than to shoot three smaller ones? That way you probably come out ahead on ammunition weight and recoil, definitely come out ahead on mechanical complexity, and large calibre bullets aren't bad at killing people.

btw, there's absolutely no need to put the forum name in your thread titles.

While this is true, you'd he shorted on the stopping power of the smaller, overlapping wounds. Also, you'd be losing your ability to use ammunition you can't take a step without tripping over in the military.

[avianmosquito]

Okay, great idea, but there are a few problems I'm seeing here. Be forewarned: I sure as hell ain't a gun expert.

If you're firing on full auto, those three-round bursts are going to deplete your ammo pretty damn fast. Besides, that ridiculous rate of fire is going to heat up your barrel fairly quickly, and you're going to get a jam. Boom. Your gun's useless now. My advice: get rid of the full auto. You can pull a trigger fast enough to put a whole lotta lead down if you need to, and the less complicated your gun is, the less likely it'll break. If you've already gotten rid of it, I apologize for the redundancy.

Only problem with that is that you stated that there's very little spread to those bullets; less than a centimeter at 100m, I believe. If you hit off-center, they're not going to get the vitals,
unless one richochets off of a rib, and that's iffy at best.

The entirety of the chest is vital organs, and that's where a marine is going to place it. A marine will put 3 5.56mm bullets through your lung in less time than it takes to form the thought.

A light machine gun that fires three times as many rounds per minute sounds and is awesome, but again, you're going to have severe cooling problems, and you're going to need to carry three times as much ammo for the same firing time. LMGs are designed for portability, and lots and lots of heavy ammunition does not lend itself to that. But sure, you may say, you can just carry the same amount of ammo and rely on its higher rate of fire! Unfortunately, accuracy doesn't lend itself well to machine guns. If I'm wrong, by all means, correct me, but the things are supposed to lay out a hailstorm of lead, not a localized thunderbolt. You might adapt this to heavy machine guns, though, provided there's enough ammunition for them; it's going to be a helluva lot easier to solve cooling in a HMG compared to a LMG.

You are, strickly speaking, correct, except that this is a different breed. This was the first dedicated suppression machine gun. It's built to make the enemy stay down with an on and off stream of lead long enough to blast their poition sky high with a satchel charge.

Is your weapon designed for use on unarmored or armored subjects, as in bulletproof vest-wearing versus non-bulletproof? Unarmored, three rounds might be a little overkill. Armored, three rounds might be of more use.

Actually, the armour would have to incredibly weak for a 5.56 to penetrate, and it typically takes a minimum of 2 shots from a 5.56 through the liver or lung.

Also, how precisely is recoil solved. If it's by a system of weights and counterweights, give me a M16 any day. Weights just make a gun too heavy and too clumsy.

[/quote]

It only delays the impulse by a fraction of a second, and the details can be found on wikipedia if you search for the only real pulse rifle in the world, the AN-94.

[Crazedwraith]

Is your weapon designed for use on unarmored or armored subjects, as in bulletproof vest-wearing versus non-bulletproof? Unarmored, three rounds might be a little overkill. Armored, three rounds might be of more use.

Actually, the armour would have to incredibly weak for a 5.56 to penetrate, and it typically takes a minimum of 2 shots from a 5.56 through the liver or lung.

So are the targets of this rifle not using armour then? If 5.56 is so shitty, why are you using it?

I thought 5.56 had good armour penetration anyway, just shitty stopping power.

[Starglider]

The quoted rates of fire /only/ make sense for the 3-round burst mode. The H&K G11 fired at an effective rate of 2200 RPM in 3 round burst mode, but this only worked because it had a fairly fancy recoil isolation mechanism. I am not clear how good the recoil isolation in these designs is, but basically it will only work if it is a slightly scaled down (and non-caseless) version of the G11, in which case it isn't really an original idea. Actually I'm not sure the G11 design would be practical with non-caseless ammo, because a conventional carbine mechanism (non-sealed with case ejection a necessary part of the cycle) operating that RoF would become extremely vulnerable to jams.

Of course cyclic rates above 1000 RPM make no sense for autofire as the recoil would be utterly uncontrollable and the ammo consumption would be ridiculous; in fact a substantially lower cyclic rate is a good idea for accuracy and ammo reasons (e.g. the G11 fired at ~550 RPM in full auto mode). Thus the 'pulse fire' mode should be the only full-auto mode, and it should have one third the cyclic rate of the burst mode.

[[R_H]]

The T22PR was introduced as an infantry weapon in 2017, and quickly caught on due to the unique way its recoil behaves. The weapon fires fast enough that it is difficult to distinguish the sounds of the individual shots, and is designed to treat these three rounds as a unit, called a "pulse," which it could fire at a rate of 600/min. Since it fires three rounds so fast, with the weapons blowback shifted pulse mechanism giving a small delay to the recoil, the rounds spread less than a centimetre at 100m. This allows the soldier to effortlessy land 3 rounds on any part of the body they need, making up for the 5.56mm round's dismal stopping power. Greater accuracy can be achieved by getting the weapon chambered in 5.45*39mm, at the expense of loosing a bit of the range and stopping power, and greater stopping power can be achieved with the use of 6.8*43mm Remington SPC, at the expense of accuracy and sheer abundance of ammunition.

What is this tripe? By the way, it would be rather difficult to make a belt-fed bullpup.

[Jeremy]

The rifle, in 5.56mm and under the designation of M36, fully replaced the M16 and FAMAS in the arsenals of the United States Marine Corps and NATO within a few years. In 6.8mm it became the standard designated marksman rifle of the US ARMY, and in 5.45mm it was quickly adopted by the spetsnaz.

Is there precedence for this?
Are the new rifles going to be used by Humans to kill Kokomes or the short giant angry lizzard guys with the long name?

[loomer]

There is no precedence for an assault rifle being adopted by nearly all (it's just missing China and India, really) major world powers, no. Similar designs, yes, but not the same damn rifle.

[Feil]

Since we're evidently allowing carbines, LMGs, and 54mm cannons, here's a notion for a sci-fi less lethal weapon:

Pump-action electro-laser gun. Call it a Shockgun. The weapon chambers a 20mm discarding capacitor with a straightforward pump action. A power supply within the weapon (or possibly a backpack power supply) powers a laser when the weapon is fired, ionizing a stream of air between the operator and the target. After 0.03s, the weapon discharges the capacitor's charge across the ionized conducting path, zapping the hell out of the target. The capacitor partially vaporizes itself in the process, and is evacuated when the next round is chambered. While at higher energies, this could kill a person, the obvious limits of such a weapon (complete inability to penetrate a bed-sheet, although clothing and non-grounded armor would likely be close enough to the person for the weapon to work through them) make it useless as an standard infantry weapon. In stead, it sees use as a Less Lethal Weapon and aboard ships and aircraft where it poses no danger of punching holes through the hull, but can reliably stop a human target. Primary purpose for use in fiction: being a shotgun that shoots motherfucking lightning.

Schk-chuk - ZAAP!

Reasonable? Mis-designed? Wishful thinking?

[[R_H]]

The entirety of the chest is vital organs, and that's where a marine is going to place it. A marine will put 3 5.56mm bullets through your lung in less time than it takes to form the thought.

If the wound doesn't disrupt the CNS or cause enough bleeding to incapacitate, someone shot through the lung is still a threat.

You are, strickly speaking, correct, except that this is a different breed. This was the first dedicated suppression machine gun. It's built to make the enemy stay down with an on and off stream of lead long enough to blast their poition sky high with a satchel charge.

So how is it fundamentally different from other MGs? They also suppress, and in addition, they kill/wound (which also suppresses). Why satchel charges?

Actually, the armour would have to incredibly weak for a 5.56 to penetrate, and it typically takes a minimum of 2 shots from a 5.56 through the liver or lung.

I'm guessing you mean the armour would have to be incredibly weak for a 5.56 to penetrate, in which case you're wrong, assuming you're talking about body armour. It does incredibly well against non-ceramic armour, better than 7.62N for example. Why the talk of livers and lungs?

It only delays the impulse by a fraction of a second, and the details can be found on wikipedia if you search for the only real pulse rifle in the world, the AN-94.

Which is comparatively a complex and expensive weapon, and hasn't seen widespread adoption by the Russians for those reasons.