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Military technology: Magic bullets

economist.com

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Re: Military technology: Magic bullets

#41

Post by almutasim »

grannyg00se wrote: post #33
icegreentea wrote: post #23

Earlier quoted context omitted.

The Hague forbids bullets that expand on penetration, on the basis that it creates larger and more traumatic wounds. This round acts more like a grenade. It explodes (and wounds/kill by shrapnel) near the target. It shouldn't actually hit the person. Completely different class of weapon. It's more accurate to call this a grenade launcher than a rifle.

It always seems so absurd to me that there are rules around wartime killing. Once you acknowledge that it is acceptable to take another person's life for profit you really have little credibility for laying out rules of fairness.

War without rules would be a greater horror. Even the ancients had them (Julius Caesar himself was charged with war crimes). How could closure and peace be negotiated, for example, without protection for emissaries.

Re: Military technology: Magic bullets

#42

Post by lusr »

jgrahamc wrote: post #30

My stab at how the bullet measures its own rotation: Suppose the bullet leaves the muzzle rotating at 300,000 RPM (quite reasonable for a rifle). That is 5kHz. It's easily within the capabilities of a Hall Effect sensor to measure a 5kHz rotation and so I'd make the very centre of the bullet contain a free rotating magnet. The rifle itself sets the magnet spinning at some known rate opposite to the rifling. When the…

Any take on why a simple timer isn't sufficient?

Re: Military technology: Magic bullets

#43

Post by mjwalshe »

nhangen wrote: post #26
sbierwagen wrote: post #16

Ah, the XM25. Last publicity blitz we saw on this was a year ago, and Gary Breacher called them out on it: http://exiledonline.com/xm25-gee-whiz-how-can-we-be-losing-w... (Even the file photo is the same!) The XM25 autocannon is neat. Absolutely nobody denies this. It's also pretty useless, because any insurgent who engages security forces in a conventional gun battle is going to die. Nine times out of ten, they're d…

That's not entirely true. There are still plenty of gunfights and ambushes being staged in Afghanistan, especially outside of the major cities.

yes its just a replacement for the existing under barrel launchers M203 and the venerable Vietnam era M79 this gives that gives you a few more tactical options.

Re: Military technology: Magic bullets

#44

Post by nohat »

jgrahamc wrote: post #30

My stab at how the bullet measures its own rotation: Suppose the bullet leaves the muzzle rotating at 300,000 RPM (quite reasonable for a rifle). That is 5kHz. It's easily within the capabilities of a Hall Effect sensor to measure a 5kHz rotation and so I'd make the very centre of the bullet contain a free rotating magnet. The rifle itself sets the magnet spinning at some known rate opposite to the rifling. When the…

They could just put a coil in the bullet and a permanent magnet along the barrel, then measure frequency produced by the temporary dynamo to calculate velocity (based on known rifling). Then use a timer to measure distance.

Re: Military technology: Magic bullets

#45

Post by mjwalshe »

bootload wrote: post #8
dimitar wrote: post #3

$25 bullets and $25000 rifles are insanely expensive. And I don't see how better rifles will bring an advantage - most coalition casualties are from mortar fire and improvised explosive traps - rebels have already lost preference for gun standoffs. But I'm sure H&K and Alliant will love to sell lots of these to whatever army is corrupt enough to buy them. Also... aren't exploding bullets illegal under the Hague conve…

"... $25 bullets and $25000 rifles are insanely expensive. And I don't see how better rifles will bring an advantage ..." Snipers are force multipliers ~ http://en.wikipedia.org/wiki/Force_multiplication

Well a "better" rifle allows you to engage at longer range Fireteams tend to have designated marksmen with Battle Rifles these days.

Also a better rifel is less prone to jamming (this is why SF's prefer the piston version of the M4)

Re: Military technology: Magic bullets

#46

Post by icegreentea »

grannyg00se wrote: post #33
icegreentea wrote: post #23

Earlier quoted context omitted.

The Hague forbids bullets that expand on penetration, on the basis that it creates larger and more traumatic wounds. This round acts more like a grenade. It explodes (and wounds/kill by shrapnel) near the target. It shouldn't actually hit the person. Completely different class of weapon. It's more accurate to call this a grenade launcher than a rifle.

It always seems so absurd to me that there are rules around wartime killing. Once you acknowledge that it is acceptable to take another person's life for profit you really have little credibility for laying out rules of fairness.

Well, most of the rules aren't about killing per se, but rather wounding. And most of the rules are in place so that the stakes of fighting never gets high enough that we would all have to stop fighting. For example, the Geneva Protocol that bans chemical and biological weapons pretty much because aside from killing, those who were wounded were an enormous burden, and terrible for morale (aside from any ethical reasons).

In that case, losing the ability to use those weapons was deemed to be outweighed by the consequences of having to deal with them being used on you. Also, since they could be potentially huge and unpredictable force multipliers, it made war all the more predictable, which is good from their perspective.

Long story short, nearly all rules of war exist because they are beneficial to abilities of the parties to conduct war. The rules do no exist to make killing fair. They exist so that parties may conduct war in a way they agree with.

Re: Military technology: Magic bullets

#47

Post by felipemnoa »

almutasim wrote: post #41
grannyg00se wrote: post #33

Earlier quoted context omitted.

It always seems so absurd to me that there are rules around wartime killing. Once you acknowledge that it is acceptable to take another person's life for profit you really have little credibility for laying out rules of fairness.

War without rules would be a greater horror. Even the ancients had them (Julius Caesar himself was charged with war crimes). How could closure and peace be negotiated, for example, without protection for emissaries.

According to history rules only matter if you loose.

Re: Military technology: Magic bullets

#48

Post by zck »

jgrahamc wrote: post #30

My stab at how the bullet measures its own rotation: Suppose the bullet leaves the muzzle rotating at 300,000 RPM (quite reasonable for a rifle). That is 5kHz. It's easily within the capabilities of a Hall Effect sensor to measure a 5kHz rotation and so I'd make the very centre of the bullet contain a free rotating magnet. The rifle itself sets the magnet spinning at some known rate opposite to the rifling. When the…

>Also says that the soldier estimates the target distance.

If the target is behind a rock, the soldier uses a laser rangefinder built into the gun to get the distance to the rock, and then inputs into the gun "the target is 2m behind the front of the rock". So, unless the explosion radius is small, the soldier has to make sure the bullet explodes behind whatever is between the rifle and the target.

Re: Military technology: Magic bullets

#49

Post by jonmc12 »

jgrahamc wrote: post #30

My stab at how the bullet measures its own rotation: Suppose the bullet leaves the muzzle rotating at 300,000 RPM (quite reasonable for a rifle). That is 5kHz. It's easily within the capabilities of a Hall Effect sensor to measure a 5kHz rotation and so I'd make the very centre of the bullet contain a free rotating magnet. The rifle itself sets the magnet spinning at some known rate opposite to the rifling. When the…

It appears to use a Ballastic computer (http://en.wikipedia.org/wiki/XM25_CDTE), like this one for iPhone: http://ballistic.zdziarski.com/

Given that this is basically an ultra-fast artillery device, the tech in this gun more likely represents a natural evolution of applied external ballistics (http://en.wikipedia.org/wiki/External_ballistics) - incidentally this is a purpose for which the ENIAC was designed. I bet the magic has more to do with being able to collect and characterize environmental data through sensors and plug these meaningfully into Ballistic models.

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