The Overloaded Soldier: Why U.S. Infantry Now Carry More Weight Than Ever • Hacker News Board

Re: The Overloaded Soldier: Why U.S. Infantry Now Carry More Weight Than Ever

#101

Post by MRD85 » Mon, Jan 07, 2019, 2:38 PM UTC

dingaling wrote: post #44

szopa wrote: post #14

This sounds insane. My hobby is medium distance hiking in (say, 250 km/155 mi na week) in the Scandinavian Arctic, so I have to carry all my food. I'm a fan of ultralight hiking, so my whole summer baggage weights around 10 kg/20 lbs excluding water. I invested some money in lighter equipment, yes, but most of my weight savings is stuff I simply do not take with me, or things that serve in multiple roles (eg. my hiki…

> avoid redundancy That's really dangerous advice for anyone inexperienced in a particular endurance activity away from contact. The military have a phrase: one is none and two are one. For anything that is life-critical, having only one is too risky.

In my survival training, the instructor taught us about our "useless" water filter. He told us that he'd only ever had to use it for real once and that one time it made it worth it to carry for every time he didn't need it.

Re: The Overloaded Soldier: Why U.S. Infantry Now Carry More Weight Than Ever

#102

Post by swish_bob » Mon, Jan 07, 2019, 2:48 PM UTC

tcpekin wrote: post #53

michaelt wrote: post #42

Earlier quoted context omitted.

According to "FM 3-05.213 (FM 31-27) Special Forces Use of Pack Animals" from 2004 [1] "Today and throughout the operational continuum, SF may find themselves involved in operations in rural or remote environments, such as Operations UPHOLD DEMOCRACY or ENDURING FREEDOM, using pack animals." [1] https://fas.org/irp/doddir/army/fm3-05-213.pdf

Wow, this document is fascinating.

I love that it includes the line: > Elephants are considered an endangered species and as such should not be used by U.S. military personnel.

Re: The Overloaded Soldier: Why U.S. Infantry Now Carry More Weight Than Ever

#103

Post by ajmarsh » Mon, Jan 07, 2019, 2:52 PM UTC

detaro wrote: post #96

rbanffy wrote: post #84

Earlier quoted context omitted.

> Ammo is really heavy Wouldn't it be possible to carry the same amount of kinetic energy with lighter ammunition? One inherent limitation of firearms is that all the energy is released inside the weapon, which has, then, to dissipate the heat and remaining gases and particles. If bullets are self-propelled, a larger part of that output can be released outside the weapon, allowing it to be faster and impart more ener…

From the few known examples, self-propelled ammunition accelerating outside the barrel means it's relatively slow when leaving the barrel, which both makes it less effective at short ranges and causes accuracy issues. Caseless ammunition is maybe a closer thing, but also tricky (heat dissipation is harder, difficulties in making ammunition robust enough). H&K made a military variant once, but no military adopted it (…

Yep, the G11. Turns out with all its other problems caseless ammo is brittle, so if you drop a round it breaks. Not super practical in the field.

https://www.youtube.com/watch?v=QGKcvM2Hh4g&t=328s

Re: The Overloaded Soldier: Why U.S. Infantry Now Carry More Weight Than Ever

#104

Post by tialaramex » Mon, Jan 07, 2019, 2:54 PM UTC

C1sc0cat wrote: post #79

AYBABTME wrote: post #37

Earlier quoted context omitted.

"one man one kit" you own your gear and are responsible for maintaining it, knowing exactly where it is at any moment, and if it fails because you didn't take care of it, it's your fault. Plus, reduces cognitive load when you know your kit like the back of your hand, in stressful situations. It's your kit and you don't lend it to others, also. Otherwise you compromise your safety.

Which is back in the day cavalry had assigned mounts - you looked after your personal mount a lot better that way.

There's an RAF anecdote related to this in Most Secret War, in which the officer asserts that his unit is more effective than other similar units because it still assigns each specific crew to a specific plane, and so knowing "their" plane they are willing to fly it despite minor problems that in other units would cause it be taken out of service for repair.

I don't have the book with me, maybe somebody else will remember and dig out the quote.

Re: The Overloaded Soldier: Why U.S. Infantry Now Carry More Weight Than Ever

#105

Post by yhoiseth » Mon, Jan 07, 2019, 3:12 PM UTC

MRD85 wrote: post #100

dsfyu404ed wrote: post #91

Earlier quoted context omitted.

Most infantrymen aren't carrying 7.62 and haven't since 'nam. The 240 is (on paper) crew served so you get to spread that load around several people. I agree with everything else though.

In a firefight, you need that ammo to get to the gun. This means it's not that easily distributed between an entire section. You're also going to need the correct sort of pouch on your armour/webbing to carry it. My experience is most of the time the majority of the gun ammo is carried by the gunner. The gun is also a lot heavier than a standard rifle.

> The gun is also a lot heavier than a standard rifle.

Good point. This is a big deal because load carried in your hands or, to a lesser degree, on a shoulder strap is more taxing than load carried on a vest.

Re: The Overloaded Soldier: Why U.S. Infantry Now Carry More Weight Than Ever

#106

Post by LanceH » Mon, Jan 07, 2019, 3:17 PM UTC

MRD85 wrote: post #100

dsfyu404ed wrote: post #91

Earlier quoted context omitted.

Most infantrymen aren't carrying 7.62 and haven't since 'nam. The 240 is (on paper) crew served so you get to spread that load around several people. I agree with everything else though.

In a firefight, you need that ammo to get to the gun. This means it's not that easily distributed between an entire section. You're also going to need the correct sort of pouch on your armour/webbing to carry it. My experience is most of the time the majority of the gun ammo is carried by the gunner. The gun is also a lot heavier than a standard rifle.

As the M60 gunner on my team (because I wasn't present when they decided who would carry it), I carried a lot more ammo. Weight was shifted, and others picked up batteries and radios that I might have carried otherwise.

sa46 addresses it a little bit above that there are different loadouts depending on how you're operating. It wasn't uncommon to move from one place to another with 100 pounds, then drop gear and patrol with a far smaller loadout.

Then again, sometimes your vehicle breaks down and you're now "man packable", which means you do need to be ready to carry a lot. This is really one of the sticking points for women in the military. It's nice to imagine that a specific job will always have a vehicle, but it is doctrine to be prepared to step into the role of infantryman.

Re: The Overloaded Soldier: Why U.S. Infantry Now Carry More Weight Than Ever

#107

Post by LeifCarrotson » Mon, Jan 07, 2019, 3:31 PM UTC

rbanffy wrote: post #84

sa46 wrote: post #38

Ah, an article I can comment on. I was an Infantry officer for 6 years and did all the normal schooling and a deployment. This is a pretty well done article. Here's some general ideas to keep in mind. - Most dismounted missions are run from trucks or an established forward operating base, so you don't carry a huge rucksack most of the time because you can just go back to your base. - Like the article states, even a d…

> Ammo is really heavy Wouldn't it be possible to carry the same amount of kinetic energy with lighter ammunition? One inherent limitation of firearms is that all the energy is released inside the weapon, which has, then, to dissipate the heat and remaining gases and particles. If bullets are self-propelled, a larger part of that output can be released outside the weapon, allowing it to be faster and impart more ener…

> Wouldn't it be possible to carry the same amount of kinetic energy with lighter ammunition?

Running just on the math, it seems the answer would be "of course":

    E_k = 1/2 m \* v ^ 2

Increasing the velocity actually increases energy much faster than increasing the mass (by, say, making bullets out of depleted uranium or tungsten). If you convert a lead (density 11 g/cm^3) bullet into aluminum (2.7 g/cm^3), you need to double the velocity to make up for the 4x loss in mass.

But we're not only concerned with kinetic energy. Momentum also matters. Or, in shooting parlance, "power factor", measured in grains (1/7000th of a pound) x velocity in feet per second. Momentum has a much closer correlation to recoil than kinetic energy. It also affects ballistics - a hypersonic lightweight round will have a different curve than a dense, merely supersonic traditional round.

Other practical concerns are also relevant: lead is an excellent lubricant/bearing material and aluminum oxide being an extremely abrasive cutting material...lead, bronze, cast iron, and other dense metals are more amenable to firing out of an interference fit with a barrel than light metals (of which aluminum is just one example, but a fairly representative one). Lead is highly ductile and mushrooms on impact, but aluminum is brittle and shatters on impact. A round fired at higher velocity spends less time in the barrel, so you need more powder, faster powder, and longer barrels to accelerate it more quickly. And the bullet is not the only thing ejected from the barrel: There's a supersonic jet of propellant gasses that contributes to both recoil and noise.

500 years of (un)natural selection in the field of ammunition materials science has left lead at the top of the charts for a good reason. Most lightweighting efforts have focused on reducing weight in the brass case, which is just packaging and becomes extra mass.

Finally, a combatant worrying about paperwork says something about the one-sided nature of recent wars: Million-dollar soliders applying overwhelming force and unimaginable funds against desperate guerillas. I wonder how quickly the slow-changing military will be able to respond if there's a war between superpowers.

Re: The Overloaded Soldier: Why U.S. Infantry Now Carry More Weight Than Ever

#108

Post by Balero » Mon, Jan 07, 2019, 3:34 PM UTC

ryanmercer wrote: post #65

gadders wrote: post #63

Earlier quoted context omitted.

True enough, but I wonder whether strength is more relevant now? I.e. they get helicoptered/driven to within 5-10 miles of their mission site with a ton of gear, rather than having to march 30 miles with their gear.

>rather than having to march 30 miles with their gear. Not all of that is just physical conditioning, there's a sizable mental component to it that helps condition you to less than ideal situations so you don't go "welp, I'm tired, fuck it, I'm sitting down to die" when you're in a bad situation and instead you're like "I got this, I've done worse, this is nothing, just a little farther" as well as equipping you to k…

"There's a reason we readopted some of these conditioning practices from ancient militaries."

I'm curious, could you expand on this, or post a link for further reading?

Re: The Overloaded Soldier: Why U.S. Infantry Now Carry More Weight Than Ever

#109

Post by pps43 » Mon, Jan 07, 2019, 3:42 PM UTC

LeifCarrotson wrote: post #107

rbanffy wrote: post #84

Earlier quoted context omitted.

> Ammo is really heavy Wouldn't it be possible to carry the same amount of kinetic energy with lighter ammunition? One inherent limitation of firearms is that all the energy is released inside the weapon, which has, then, to dissipate the heat and remaining gases and particles. If bullets are self-propelled, a larger part of that output can be released outside the weapon, allowing it to be faster and impart more ener…

> Wouldn't it be possible to carry the same amount of kinetic energy with lighter ammunition? Running just on the math, it seems the answer would be "of course": E_k = 1/2 m \* v ^ 2 Increasing the velocity actually increases energy much faster than increasing the mass (by, say, making bullets out of depleted uranium or tungsten). If you convert a lead (density 11 g/cm^3) bullet into aluminum (2.7 g/cm^3), you need t…

> lead is an excellent lubricant/bearing material

Modern projectiles are jacketed so lead never touches anything.

Re: The Overloaded Soldier: Why U.S. Infantry Now Carry More Weight Than Ever

#110

Post by Balgair » Mon, Jan 07, 2019, 3:44 PM UTC

ajmarsh wrote: post #103

detaro wrote: post #96

Earlier quoted context omitted.

From the few known examples, self-propelled ammunition accelerating outside the barrel means it's relatively slow when leaving the barrel, which both makes it less effective at short ranges and causes accuracy issues. Caseless ammunition is maybe a closer thing, but also tricky (heat dissipation is harder, difficulties in making ammunition robust enough). H&K made a military variant once, but no military adopted it (…

Yep, the G11. Turns out with all its other problems caseless ammo is brittle, so if you drop a round it breaks. Not super practical in the field. https://www.youtube.com/watch?v=QGKcvM2Hh4g&t=328s

Yes! Forgotten Weapons is an amazing channel. I love Gun-Jesus (Florida-Man Edition), aka Ian. His simple, clear, engaging style is fantastic. The deep dives into engineering and history are fantastic. Infinitely bingeable.