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Silly designquestions for you all
Hardraade

Posted on 12/30/2012 8:35:51 AM PST by Hardraade

This is a typical howto-question.

Take a typical 7.62 bullet. Posit that it knows exactly where it is, and where it should be.

How do you change direction, with the equipent being small enough to fit onboard with the position sensor?


TOPICS: Hobbies
KEYWORDS: ammunition; magicbullet; vanity; weaponry
Ping to any and all tinkerers and lovers of things that go bang.
1 posted on 12/30/2012 8:35:57 AM PST by Hardraade
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To: Hardraade
http://www.gizmag.com/sandia-self-guided-bullet/21286/


2 posted on 12/30/2012 8:43:32 AM PST by HangnJudge
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To: Hardraade

Point the gun barrel in a different direction.


3 posted on 12/30/2012 8:44:49 AM PST by outofsalt ("If History teaches us anything it's that history rarely teaches us anything")
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To: HangnJudge

http://www.military.com/video/ammunition-and-explosives/ammunition/sandia-laboratories-self-guided-bullet/1432222481001/


4 posted on 12/30/2012 8:46:14 AM PST by Paladin2
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To: Hardraade

5 posted on 12/30/2012 8:47:13 AM PST by HangnJudge
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To: HangnJudge
And so we come full circle - to smooth bore weapons.
I guess even a sabot round would be spun by the rifling... unless the projectile were disassociated from the sabot casing via (real tiny) ball bearings.

Heh.

6 posted on 12/30/2012 8:51:39 AM PST by grobdriver
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To: Hardraade

Fire it from a smart phone. There’s prolly an app for this.


7 posted on 12/30/2012 8:52:28 AM PST by umgud (No Rats, No Rino's)
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To: Hardraade

Newton’s Laws of Motion?


8 posted on 12/30/2012 8:54:59 AM PST by 1rudeboy
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To: Hardraade

My question is why would someone want such a bullet? “Smart” bombs made defeating enemies nearly impossible. They made people expect that so-called “innocents” would not be harmed and led to the staging of collateral damage which the liberal media love to cover. “Smart” bullets would further that fallacy and the media would use the unrealistic expectations of technology to further push their anti gun agenda. No thank you.


9 posted on 12/30/2012 9:03:22 AM PST by ConservaTexan (February 6, 1911)
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To: grobdriver

IIRC, the sabot, at least in an M-1 Abrahms isn’t even formed until striking the target. The entire round could be considered a sabot, I guess, but the killing part comes on impact.


10 posted on 12/30/2012 9:12:59 AM PST by Gaffer
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To: ConservaTexan

“Innocents not be harmed...” Yeah, slippery slope.

Brain Storm: How about cops use smart bullets that guide on bad guys. Or just ‘wing them’.

(I want to throw in a Will Rogers comment about a headline: ‘Innocent New Yorkers shot on the street’ and he says ‘That’s the best shooting ever done in this town. Hard to find four innocent people in New York.’)

Now how to designate a bad guy? Implant a chip? Image recognition of someone holding a gun? Facial image comparison with NSA data base?

Or home on images of 4-legged fur-covered objects with wagging tails.

In reality a 7.62 has so much linear and rotational inertia it would be hard to get a control surface big enough to deflect its ballistic path very much. Note how the .50 cal has about 4 times the original bullet size for the new tail.


11 posted on 12/30/2012 9:34:59 AM PST by Scrambler Bob (Honk Honk - I am the Goose that laid the Golden Eggs - so far ....)
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To: Gaffer
The case of a sabot round (the sabot) falls clear after exiting the muzzle.
Only the projectile continues down range.

http://en.wikipedia.org/wiki/Sabot

12 posted on 12/30/2012 9:36:31 AM PST by grobdriver
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To: grobdriver

I know that part. Like the plastic surround a sabot slug in a load-your-own muzzle loader.

I was talking more about the actual final sabot that is formed on an M-1 Sabot round shell.


13 posted on 12/30/2012 9:39:23 AM PST by Gaffer
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To: Scrambler Bob

I also like the possibility that if a bad guyl/gal is shooting at me I may be a better shot than him/her.


14 posted on 12/30/2012 9:41:35 AM PST by ConservaTexan (February 6, 1911)
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To: Gaffer

The Sabot “bullet” has a lightweight, full caliber outer shell, and a sub-caliber, high density ‘core’ specifically shaped for penetration. Upon impact the outer shell is stripped off, and the high l/d ratio core has much concentrated energy to enable penetration.


15 posted on 12/30/2012 9:43:58 AM PST by Scrambler Bob (Honk Honk - I am the Goose that laid the Golden Eggs - so far ....)
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To: Scrambler Bob

That’s essentially what I already said in #6 for the M-1 Sabot Round.


16 posted on 12/30/2012 9:46:41 AM PST by Gaffer
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To: Gaffer

Sorry, my engineering past has emerged. In my terminology, the sabot is the outer shell. The sabot does not form on impact, but already has its form at launch and covers the penetrator till impact.

But yes, the M-1 sabot is a tank killer.


17 posted on 12/30/2012 9:57:56 AM PST by Scrambler Bob (Honk Honk - I am the Goose that laid the Golden Eggs - so far ....)
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To: Gaffer
There is no “final sabot” formed on a sabot round. There is a kinetic energy penetrator that is very narrow and long and fin stabilized. The sabot separates right after leaving the barrel and the penetrator continues traveling at about 5000 feet per second.

The other armor piercing round is the HEAT (High Explosive Anti Tank) round. This round has a shaped charge embedded in the shell and detonates at a precise distance from the armor, sending a nearly pinpoint jet of hot gas into the armor, hopefully breaching that armor.

18 posted on 12/30/2012 9:58:16 AM PST by OldMissileer
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To: grobdriver; Gaffer
"And so we come full circle - to smooth bore weapons. I guess even a sabot round would be spun by the rifling... unless the projectile were disassociated from the sabot casing via (real tiny) ball bearings."

The original M1 Abrams had the same M68 105mm rifled cannon as the M60A3.

The M1A1/M1A2 upgraded to the Rheinmetall M256 120mm smoothbore (also used on the Leopard 2 and the ROK K1A1). Spin-stabilizing (i.e. "rifling") a projectile at the velocities of the 120mm sabot round would actually result in the projectile veering in flight in the direction of the spin, so designers went with fin stabilization and a smoothbore cannon. The sabots do in fact, discard in flight...


19 posted on 12/30/2012 9:59:09 AM PST by Joe 6-pack (Que me amat, amet et canem meum)
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To: Hardraade

Change your position and fire again. Simple is usually better and cheaper.


20 posted on 12/30/2012 10:00:00 AM PST by muir_redwoods (Don't fire until you see the blue of their helmets)
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To: Gaffer

I think you are referring to the plasma jet formed by the Munroe effect when a High Explosive Anti-Tank (HEAT) round strikes its target.

http://en.wikipedia.org/wiki/Shaped_charge

The sabot in an anti-tank round is a spacer that keeps the long tungsten (or, in the case of the M1, depleted uranium) penetrator centered in the shell casing during handling and initial firing. Since the penetrator is essentially a large, very hard dart, a base plate is needed to allow the expanding propellent gases to deliver their full power to the penetrator; otherwise, they would just blow past it. Once the penetrator, sabot, and base plate exit the bore of the cannon, aerodynamic forces peel the sabot and base plate away and allow the penetrator to speed to the target, usually at speeds well in excess of 4000 fps. These rounds are referred to as Armor Piercing Fin Stabilized Discarding Sabot (APFSDS) rounds.

While both deliver kinetic energy to the target, the HEAT “penetrator” is created only at the moment of impact. The penetrator in the APFSDS is manufactured component of the round.

As for the Sandia self-guided bullet, it might have useful applications in sniping, if you can get the electronics to survive the shock loads from firing and the guidance mechanism to function properly. Not an easy task, even in a much large diameter round. See, for example:

http://en.wikipedia.org/wiki/Extended_Range_Guided_Munition


21 posted on 12/30/2012 10:00:10 AM PST by Captain Rhino (Determined effort is the hammer that Human Will uses to forge Tomorrow on the anvil of Today.)
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To: Captain Rhino

Aha!


22 posted on 12/30/2012 10:04:11 AM PST by Scrambler Bob (Honk Honk - I am the Goose that laid the Golden Eggs - so far ....)
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To: Captain Rhino

Gaffer,

By the time I got my post written and well...posted, several others had already answered.

Sorry for the late hit.


23 posted on 12/30/2012 10:04:41 AM PST by Captain Rhino (Determined effort is the hammer that Human Will uses to forge Tomorrow on the anvil of Today.)
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To: Captain Rhino

Gaffer,

By the time I got my post written and well...posted, several others had already answered.

Sorry for the late hit.


24 posted on 12/30/2012 10:04:50 AM PST by Captain Rhino (Determined effort is the hammer that Human Will uses to forge Tomorrow on the anvil of Today.)
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To: muir_redwoods

You get only one shot.

I had considered microfins or vanes, but they’ll likely interfere with the spin which I need for other functions (power and clock). Maybe tweaking the things internal weight balance would be the way.


25 posted on 12/30/2012 12:07:02 PM PST by Hardraade (http://junipersec.wordpress.com (Vendetta))
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To: muir_redwoods

You get only one shot.

I had considered microfins or vanes, but they’ll likely interfere with the spin which I need for other functions (power and clock). Maybe tweaking the things internal weight balance would be the way.


26 posted on 12/30/2012 12:07:43 PM PST by Hardraade (http://junipersec.wordpress.com (Vendetta))
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To: Hardraade

A fluid gimballed INS system with backup starshots at the top of the ballisic arc like the MX?


27 posted on 12/30/2012 12:32:53 PM PST by gura (If Allah is so great, why does he need fat sexually confused fanboys to do his dirty work? -iowahawk)
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To: Hardraade
How do you change direction, with the equipent being small enough to fit onboard with the position sensor?

I have pondered this one for a long time.

The answer, I believe, is lift vector modulation.

Look up and read about how the Gemini and Apollo capsules changed directions. The answer was an off-axis thrust that changed the effective center of gravity, which caused lift in a particular direction.

Well, that isn't very practical in a bullet spinning at 50,000 RPM or more. The answer there is a spin-angle sensor and a peizoelectric actuator with a weight on it, controlled by a microcomputer.

In the relaxed position, the weight is in the center of the bullet, and the lift vector is neutral: bullet goes straight forward.

To move to the side (or any radial direction), the actuator is used to push the weight slightly off-axis for a certain number of degrees of rotation, in the opposite direction that the bullet needs to go. This is repeated for a number of bullet rotations proportional to the desired turn angle, and inversely proportional to the actuator weight. This alters the lift vector and "turns" the bullet in the desired direction.

I think the whole thing would have to be micromachined on a single chip, kind of like the digital micromirrors in a cinema projector. It would take very little electrical power, yet would require high voltages for the actuator. But I think it could be done.

28 posted on 12/30/2012 3:54:08 PM PST by backwoods-engineer ("Remember: Evil exists because good men don't kill the gov officials committing it." -- K. Hoffmann)
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To: Hardraade

Sandia’s Self-Guided Bullet Prototype Can Hit Target A Mile Away
armedselfdefense.blogspot.com ^ | 02/01/2012

Posted on Wednesday, February 01, 2012 1:10:09 PM by Sasparilla
http://www.freerepublic.com/focus/bloggers/2841187/posts


29 posted on 12/31/2012 12:38:04 AM PST by Kevmo ("A person's a person, no matter how small" ~Horton Hears a Who)
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To: Hardraade

30 posted on 12/31/2012 12:44:25 AM PST by Lancey Howard
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To: Kevmo; backwoods-engineer

As I said before, sort of, Sandia is microfins/vanes and will interfere with the other stuff I want in my magic bullet, like the spin which will provide clock and also power for computation.

Basically, I want long-range fire-and-forget from a rifle that is outwardly just another sporting rifle, maybe even a simgleshot.

Lift vector modulation sounds promising.


31 posted on 12/31/2012 3:22:16 AM PST by Hardraade (http://junipersec.wordpress.com (Vendetta))
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To: Kevmo; backwoods-engineer; MestaMachine

Anyway: what I’m after is the technology for a militia. And not just this thing.

It should be items and concepts that the government (any government) does not have, let’s say a lead of 10-20 years. That, gentlemen, is way easier than it sounds. One of the H&K specialty items is almost certainly mine, grabbed by our verson of DARPA many years ago when I was required by law to let them have first look. But we have some of the smartest ppl I know, right here on FR. We can probably outrun what the establishment has become.

How about a traditional muzzleloader that looks innocent but is able to take out an office building? Way easy.

Micromachining was mentioned here, would that be a track for 3d-printing?


32 posted on 12/31/2012 6:35:28 AM PST by Hardraade (http://junipersec.wordpress.com (Vendetta))
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To: Hardraade

As I said before, sort of, Sandia is microfins/vanes and will interfere with the other stuff I want in my magic bullet, like the spin which will provide clock and also power for computation.
***Firing a small battery as part of the terminal mass on target will give you power and with a 555 timer, a clock. Once you free yourself from rifled barrels, you could further disguise your prize by having it not even look like “just another sporting rifle” in the first place, by screwing in the barrel at the last moment you intend to use it. To further the disguise you could add plastic to the outside and make it look like a camera, or a wok, or a radio or whatever — rather than looking like a sporting rifle is still going to draw attention to you. Why are you limiting yourself to 7.62? Basically you need more room for whatever electronics and magic you want to add, which is why the DARPA project is going for .50 caliber.


33 posted on 01/01/2013 11:32:04 AM PST by Kevmo ("A person's a person, no matter how small" ~Horton Hears a Who)
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To: Kevmo

Darpa, bah.

There’s two reasons I want a plain vanilla hunting bullet/rifle setup:

1. Appearances.

2. Regulation. Expect the 50BMG to become a threatened species, and the Barrets and others likewise.

Now, of course, when we’re looking at “traditional” muzzleloaders we have flexibility. These things will never get banned, and they can fire bullet sizes dmn near to a torpedo. So we’ll be looking at agents. And there are agents much easier to procure, easier to handle, and deadlier than a nerve load. And not listed as WMD, either.


34 posted on 01/01/2013 1:31:43 PM PST by Hardraade (http://junipersec.wordpress.com (Vendetta))
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