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DARPA Developing Defensive Plasma Shield
galactic_grub writes "According to an article at New Scientist, DARPA is developing a plasma shield that would allow troops to stun and disorientate enemies. The system will use a technology known as dynamic pulse detonation (DPD), which involves producing a ball of plasma with an intense laser pulse, and then a supersonic shockwave within the plasma using another pulse. The result is a gigantic flash and a loud bang in a the air. 'The company has also pitched a portable laser rifle, which would be lethal, to the US Army. It would weigh about fifteen kilograms, would have a range of more than a mile, and could have numerous advantages over existing rifles - better accuracy and the ability to hit a moving target at the speed of light.'"
I imagine it would be used for crowd control or hostage situations. There are many situations where non-lethal force is needed against an enemy.
If there is to be a balance of power of any kind.
What?
plus disorienting may be more valuable when it comes to groups you cannot guarantee an instant kill on.
in other words, disorient then kill if necessary, a kill shot is not a guarantee but if you can keep them from taking any real action you open yourself more options, which includes a few important seconds to kill the baddies. think hostages, who cares if you give the hostage a headache or such, its better than the baddies getting shots off at him if you only wound one.
let alone the fact that the public seems to take a dim view lately of actually killing enemies...
* Winners compare their achievements to their goals, losers compare theirs to that of others.
Depends on what the laser is tuned for. If it's tuned for cutting, then yes, it will leave a cauterized hole. But if it's tuned for energy transfer (think: turning water to steam), it's more like being shot with an exploding bullet.
"They redundantly repeated themselves over and over again incessantly without end ad infinitum" -- ibid.
The Barrett M82A1 sniper rifle, presently in service with the U.S. military, weighs 33 lbs. (It's not clear from Wikipedia whether this is loaded or unloaded -- with .50 BMG ammunition, this is not a trivial consideration, but we'll assume it's the loaded weight.) Even the M40, the military variant of the Remington 700, weighs 16 pounds. Both are commonly supported with bipods, so it's clear that this weight is by no means out of the range of what's acceptable for use by snipers.
Weight in a conventional firearm actually has some significant benefits, reduced recoil being chief among them. This isn't the case with lasers, obviously.
The AK-74 and its variants fire 5.45x39. "NATO ammo" would be 5.56x45, so, no, an AK-74 wouldn't be able to chamber let alone safely fire NATO ammo. I've heard some 74s were converted by former east bloc countries to shoot 5.56 once they joined NATO.
You can also get 7.62x39 AK uppers for AR-type rifles and I guess Alexander Arms made 5.45x39 uppers as well, but still, box stock AK-74s and M16s and variants are not capable of shooting each other's ammo.
Well, I have no response to your comments on armor, but I'd like to address some of your assertions on the M16 vs. the AK-47. Yes, it's a bit off topic, but misinformation shouldn't be left to spread, and apparently nobody else is going to step up.
.223 Remington), and the AK-47 fires 7.62mm rounds (7.62x39mm, commonly called "7.62 Russian"). For comparison, the NATO 7.62x51mm standard is similar to the civilian .308 Winchester.
Onto your comments about the Kalatchnikov. There are lots of reasons to like the Kalatch over the M-16. There are a few to like the M-16 over the Kalatch.
It's "Kalashnikov". Nobody refers to this weapon as a "Kalatch". The only reference I could find for this spelling with a quick Google search (other than a place name) is the "Remember Jenin" e-mail which made the rounds some time ago. One reason not mentioned below to prefer the M16 is the loud report of the Kalashnikovs. The Kalashnikovs are easier to field strip, but they have a small pin (I forget its correct name) which is too easy to lose; and, no, the tiny pin on the extractor assembly of the M16 is not analogous - you shouldn't disassemble that in the field. Note that the later AK-74 design corrected that problem with field stripping. From the perspective of procurement, the AKs are more common and perhaps more suitable for poorly trained groups, but they're also more likely to be badly manufactured, including the ammunition. More corrections follow.
The Kalatch is a higher calibre weapon than the M-16. So the bullets reach the target with significantly more Kinetic energy.
At least you're correct about the caliber: The M16 fires 5.56mm rounds (NATO 5.56x45mm, much like a civilian
However, you only get partial credit on kinetic energy: At 100m the 7.62 Russian has roughly 15% more kinetic energy than the 5.56 NATO. Beyond that, the energy of the 7.62 Russian declines much faster than the 5.56 NATO. At 300m, the 5.56 NATO has about 25% more energy, and at 600m it has about 3 times the energy of the 7.62 Russian (yes, this is well beyond the AK's effective range). Ballistics information for this should be available online. I haven't found a good study of the relative effectiveness of these arms on modern infantry armor, although anecdotal reports are fairly common.
Both the Kalatch and the M-16 have an effective battle range of 25-300 yards.
Half right again, it seems. Most sources do credit the AK-47 with an effective range of 300m. But the effective range of the M16A1 was 450m, and it's supposedly 550m or 600m for the A2 and A4 designs (depends on the source). I cannot attest to the validity of the 600m figure, as I've mostly fired the M16A1; I was discharged before the M16A2 was issued to my unit.
The Russian Kalatch's are quite well made, and some of the Hungarian ones are also.
The Russian AK-47 rifles (except for early models) have milled receivers, which are much better than the stamped receivers found in most others, such as the cheaply made Chinese knock-offs. The subsequent and more common AKM design has a stamped receiver, but it has welds and other structural improvements which make it superior to the original stamped receivers, and as good as the milled receivers while being lighter. Some of the AKs manufactured in the former Soviet Block nations are also reputed to be of good quality, but I don't know anything of those made in Hungary; based on the accuracy of the rest of your claims, I doubt you do either.
The Kalatch doesn't jam anywhere near as much as the M-16, partially because it uses so much more gunpowder/bullet.
The reliability of the AK rifles in dirty conditions is mostly due to the simpler design, the intentionally looser fit (lax tolerances) of its parts, and the chromium plating on key parts to avoid corrosion and pitting. AK rifle designs in 5.56 NATO and other calibers have similar reliability characteristics. The c
"Geneva Convention "war". Works pretty well. Won in WWII and Korea."
The Korean war was a limited war because it was restricted to Korea itself despite the fact that China directly intervened by sending huge numbers of men who directly fought against UN forces, and defeated them on a number of occasions, inflicting heavy casualties in the process. In a WWII-style conflict, this would have resulted in massive retaliation against China itself, probably by dropping atomic bombs on Chinese cities, which MacArthur was seriously considering before being replaced (the fact that China had no airforce would have made this a low-risk affair in a military sense, but the possibility of direct USSR intervention meant that it was very politically risky).
Note also that we (i.e. the UN forces which were predominantly but far from exclusively US forces) did not win the Korean war, because it ended in a stalemate which culminated in a ceasefire agreement that essentially established the same North / South border that had been in place before the war. This ceasefire is still in place, so the war hasn't officially ended, hence a half century long armed stand-off between the two opposing sides. This wasn't the goal of the US / UN side, or the one the North Koreans had, although it does seem to have been what China wanted (the Chinese didn't intervene until UN forces were near to their borders with North Korea; they'd warned the UN that this would happen on several occasions, but the CIA told Truman they were bluffing, so the warnings were ignored). It would therefore be fair to say that the only true winner was China, while both the UN / US and North Korea can be regarded as net losers because neither managed to realise their military or political goals.
I'm not going to change your sheets again, Mr. Hastings.
I wouldn't recommend regularly standing next to walls during urban combat. Bullets have this odd tendency of ricocheting and following the walls... The winner is the one who keeps his cool, knows what he's doing, and actually hits his target. Unless you're a marine; then you can just shoot everything that moves and hope you survive the encounter. Or Navy, then you can just kinda sit on a boat and know that they can't reach you very easily. Or if you just want a free purple heart license plate to reduce the odds of getting a speeding ticket. Outside of those reasons, I really don't see a huge value in cowering next to walls.
SWM seeks new sig for a brief fling
1.) As was already pointed out, a pulsed laser strong enough to kill is strong enough to ionize the air it travels through, generating a glowing line straight from the firer to the victim. Even seeing that line for a fraction of a second allows people to deduce the rough direction from which the shot came - that's what our brains are made for.
2.) I'm not entirely sure about this one, but I think that the ionized air gives off a fizzing sound, which means that yes, it becomes possible to identify a laser sniper by sound. Also, light bounces off the victim, resulting in at least a small flash as (s)he gets hit. No inexplicable deaths.
I think the advantages are more along the line of "we get long-range kills without having to calculate the effects of wind and gravity" than "our snipers become undetectable".
USE HOT GRITS WITH STATUE OF NATALIE PORTMAN (NAKED AND PETRIFIED)
It's a nonsense statement, then, since with modification most guns can fire pretty much any ammo.
Saying an AK-74 fires NATO standard rounds with modification is really like saying AK-74 doesn't fire NATO rounds without modification, and with modification it can fire pretty much any round.
Daisycutter refers to the tube attached to the tip of a bomb that allows the bomb to detonate before the main body has touched the ground and have less of the blast absorbed by the ground. These days we have so many electronics in bombs I'd expect there's some kind of sensor that detonates the bomb at an optimal height without adding any long tubes to the thing.
Justice is the sheep getting arrested while an impartial judge declares the vote void.
All of this is without mention of the AK's reliability, which is demonstrated quite vividly, I think, by Vietnam veteran David Hackworth:
I could see an urban-based NATO soldier taking up an AK-47 for those reasons; Stopping power, reliability, ammunition availability, and good-enough accuracy for the setting, with the added effect of the larger bullet being able to penetrate certain types of walls, not to mention full-auto capability (M-16A2's don't have such a setting ; M-4's do). Plus, it leaves their more expensive NATO counterparts in conditions of less wear and tear for future battles while they're making use of the Kalashnikov's in urban combat.
Screw the rules, I have green hair!