Sci-fi soldiers with bulky armor brace their rifles on their chest plates. What do their rifle stocks look like?

Question

The sci-fi soldiers have bulky$^1$ armor that gets in the way of traditionally shouldering a rifle. They brace their rifles on their chest plates instead. Conditions are otherwise similar to modern combat. They've been doing this for long enough for their military to catch on and procure a rifle stock better suited to their needs

Real rifle stocks are obviously a case of form-follows-function to fit a human shoulder. If the design purpose has changed and stocks now go up against a big plate of armor (which might itself be modified with a ridge, indentation, etc to help support the rifle, if that's useful) how would form follow function?

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1: Think Doom Guy, all the guys in HALO, Imperial Stormtroopers, 3/4 of the armor from Mass Effect, all the guys in Starship Troopers, all the soldiers in Warhammer 40,000, etc, etc. It's not that they can't touch a rifle butt to their shoulder (or the armor over their shoulder), it's that the armor keeps the shoulder from making a stable pocket to support the weapon.

Answer 1

And Gun Jesus did Spake and say:

"Lo, For thine problem didst already exist in thine obscure cavalry rifles from the 19th century"

And Forgotten weapons did publish a Blog post about it: And the people saw that it was good.

And here's the link when Ian get's his own.

Okay - Serious answer time - Forgotten Weapons is an excellent resource for Firearm design and history - and as it turns out - the French had a similar problem - which is they wanted their armored Cavalry (Cuirass) to use a Carbine (shorter than a full-length rifle) - the Metal armor made getting a Cheek Weld hard and wood on metal made getting a good shoulder position hard - the result? The above rifle.

To answer the question a different way - there would be no Buttstock.

A buttstock has a number of functions:

1: Balance the weight of the Barrel
2: give a comfortable length-of-pull
3: Bring the sights of the rifle up to the eyeline
4: Recoil mitigation.
5: Storage

So let's go through them

• Balance. Well, if you are chest-bracing the Rifle, I think it's safe to say that it's both a big-ass gun and also, the counterbalance is your entire body

• Length of pull. No longer an issue - you could look at the Smart gun from the Alien universe for this one - as to how that is held for a comfortable feel.

• Sights. Again, Nope - if we are firing from the chest, either we have some form of periscope'd Optic or more likely, since we are Sci-Fi soldiers, we would use something similar to the Apache Gunships Helmet sight that is slaved to the Gun - that is, the Helmet would feature it's own targetting system that is either slaved to the gun (if the Gun has the ability to move) or simply displays the point of impact. (will cover in more detail in a min)

• Recoil Mitigation. Nope - that's now done by a combination of your chest and the weight of the armor.

• Storage. Nope - Storage in a Buttstock is more about utilizing 'dead space' - so if there's no Buttstock, there's nothing to utilize.

What I would envision is some form of ball joint and a semi-permanently attached firearm, possibly servo-assisted/stabilized (like the Alien Smart Gun). You could also look at Drumline Harnesses as an idea for something that relatively quickly attaches/detaches, has a degree of movement (going from a 'deployed' position to a 'moving' position).

The Ball-joint is your recoil mitigation, the harness is your weight balance, a smart helmet/integrated optic is your aiming system - and you don't need to worry about length of pull or additional storage.

Answer 2

Your question reminds me of the problem NASA faced when sending the astronauts to the Moon: due to the bulky space suit and helmet they were wearing, they could not use a conventional Earth camera, so NASA engineered a chest camera and trained the astronauts in using it.

One of the major challenge was, and will be also in your case, the aiming: instead of aligning the axis of the lens/rifle with the target, they will need to look toward the target and trust that the alignment is according to their line of sight.

While the astronauts didn't have a narrow zoom and a coarse alignment was sufficient (the rather wide field of the camera would allow for a decent image) with a rifle it could be a different story, unless they are wearing a shotgun like rifle.

Therefore I think that some optics allowing the bearer of the armor to see what they are aiming at with the rifle mounted on their chest, and adjust accordingly: a periscope with a viewfinder would be the simplest solution.

Answer 3

Stocks are not always better than no stock

While a stock gives a firearm a number of advantages, it also comes with its drawbacks.

Pros:                         Cons:
- Better recoil control       - Added weight
- Reduces hand-shock          - Limits the postures the weapon can be fired from
- Easier to aim               - Can become cumbersome in urban combat or other tight spaces

While most infantrymen agree that a stock is better than no stock, SWAT teams and vehicle crews often find that the stock inhibits them more than it helps; so, they will often be fielded with stockless firearms like the tactical shotgun or SMG shown below.

So, if your infantry already has too much armor for a stock to make since, it is probably because they are close-combat shock troops, in which case, they will find many advantages in ditching the stock anyway.

With Power Armor, your hand "becomes the stock".

Most of the future-tech settings the OP brought up don't just give soldiers thick heavy armor. They give them Power Armor. This is important because in addition to added protection, power armor can fulfil all of the roles that a stock is meant to serve which would make a stockless firearm universally more versatile in thier hands than one with a stock.

Using the the same sort of technology that cameras use to compensate for wobbling free-hand shots, your power armor could auto-correct the aim of a soldier by synchronizing the armor with sensors on the firearm itself. Even with a stock, a human can't accurately aim more than a few hundred meters without extensive training, but AI assisted riffles exist today that allow an amateur to accurately hit targets a kilometer away. So, with a little bit of auto-correction, you can overcome any need for better recoil control or easy of aim because your computer assistance is doing that part for you. The soldier just needs to point the gun more-or-less at the target to be able to shot it.

This just leaves the hand-shock issue which again can be nullified by the fact that you are holding the firearm with a robotically augmented grip. The recoil will simple go through your gauntlets and into the frame of your power armor instead of into your hand.

Since the power armor is doing the job of a stock, you get the better flexibility of a stockless firearm with out any of the drawbacks.

Why not a shoulder or chest mounted weapon?

When you mount a firearm directly to the body, it limits your ability to fight around your terrain. You can't use a chest cannon from a deep trench or prone position, and any position you can use it from generally involves exposing a much larger portion of your body to shoot. Shoulder cannons are a bit better, but limited when fighting around a corner or through a murder hole. Also, both options are a major sang risk when moving through woods, ruins, or other kinds of tight terrain, because a gun in the hand can be rotated a lot more ways to unsnag it.

Cover is one of the most important tactical considerations in any firefight because it both obscures your presence allowing you to shoot before you get shot, and it also minimizes your exposed body area making you a more difficult target to hit. Also, it takes more time to "step-out" to shoot a mounted weapon vs just reaching or tilting around a corner which gives the enemy more time to react.

When you use a hand-held firearm, you can reposition it relative to your body based on your combat situation; so, no matter what situation you are facing, you can always lead with your gun without having to expose a significant part of your body.

Answer 4

I'd suggest that it depends in part on just how bulky the armour is. The optimum would probably to have a ball-and-socket joint between the armour and stock, and since it would be undesirable to reduce the thickness of the armour that implies that the futuristic infantryman would have balls (or at least hemispheres) in the region of his shoulders and chest to support the butt end of a drastically-lightened projectile weapon.

Answer 5

Nothing. Power armor won't use rifle stocks because the reasons for stocks are all eliminated by the armor itself. (bracing for improved aim and to handle recoil)

I've often wondered why we don't (currently) have heads up display red dots. I should be able to draw and fire from the hip with my red dot showing on my glasses. There's nothing special about looking down the barrel. It's trivial to mount a camera on the barrel and project a dot on your visor showing exactly where your gun is pointed. Nintendo had the technology decades ago (how do you think duck hunt knew if you hit the duck?)

Your fancy power armor better have that. At which point there's no need to raise the thing to eye level. The other purpose of the rifle stock is bracing both for aiming and recoil, neither of which you'd need because your power armor does it for you (and future ammo probably has less kick). I'm not even sure you need a rifle. Mount the barrel on the forearm and your space marines are always armed.

"If I got arms I'm armed. ooh ra."

Also, bullets are so 20th century. Don't you think we'll bring drones down to a small size in the coming centuries? Or tiny rocket powered missiles? Imagine a backpack full of bees. Bees with explosive bellies or with plasma cutters. Target with your visor and turn them loose. Or if you want a gun why have the meat computer do the targeting? Silicon is so much more precise. Just mount a turret on the shoulder and let the computer do the targeting.