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John Gearing
12-13-2002, 09:23 PM
Okay gang, here's the deal: I need to shoot a special high velocity round into something that will let me retrieve the bullet at least somewhat intact. Here are the specs: it will be a 55 grain bullet traveling at close to 4100 feet per second. The good folks at the State Crime Lab, with whom I'm working on this project, figure that if they shoot into their water tank (as they would normally do) all we'll get back is "dust", and on the basis of an independent expert I've been talking with, I agree with them. An obvious solution is to remove the bullet, dump out a bunch of powder so that the velocity will come down to a nice low level, and then re-seat the bullet and shoot into the water tank. But here's the rub...this is a rather special type of ammo that is very difficult to disassemble without causing damage and which would require some special tooling to reassemble. So I throw the question to ye mighty wizardes of the woodenboat forum!! One of my thoughts was to build a tube full of ballistic gelatin (with overflow ports every so often) and fire into that. Any other thoughts???

Chris Coose
12-13-2002, 09:28 PM
Piss Donn off and shoot him when he comes to kick your ass.

rodcross
12-13-2002, 09:30 PM
Water is too dense, as is gelatin. You need a different medium.

4,100 fps? What the Hell are you working with?

Pete Dorr
12-13-2002, 09:40 PM
http://www.kraftfoods.com/jello/images/jlo_pudding_box_pix.jpg ?

Mrleft8
12-13-2002, 09:43 PM
I suggest shooting it into a tube with compressed air heading towards the muzzle at a rate of 55 grams @ 4100 fps. or whatever that equals in PSI...

Memphis Mike
12-13-2002, 10:26 PM
Sand

Ross Faneuf
12-13-2002, 11:00 PM
A really long snow bank. But finding the round will be exceptionally tedious.

This actually works, BTW.

4100 FPS?????

Remove me from this thing.
12-13-2002, 11:05 PM
I think most 55gr bullets going 4100 fps would disintegrate in the air, so what kind of round is this? That's the fastest .22 round I have ever heard of, BTW.

Stan? Seen anything like this on the Reloading Bench?

Mrleft8
12-13-2002, 11:18 PM
Sounds like a frangible ceramic round to me.....

Meerkat
12-13-2002, 11:32 PM
Uh, this might be silly, but a few dozen loaves of bread stacked end to end?

Peter Malcolm Jardine
12-14-2002, 12:00 AM
Correct me if I am wrong, but one of the reasons that the bullet would have problems in water, is the immediacy of the change in density.... if thats true you need a graduated density to absorb the impact of the bullet. Shooting into released compressed air... a wind tunnel of sorts? but very high pressure. hmmm.. cool problem.

rodcross
12-14-2002, 12:22 AM
Now here's a hairbrained thought: Silly Putty! It will shatter at the initial impact and will continue to shatter until the velocity is dimished to the point where the putty will offer a high resistance soft landing Check with Sikorsky or UT. The stuff was designed for aircraft shock absorbers in the first place.

stan v
12-14-2002, 06:35 AM
John, I believe in the most recent edition of Handloader Magazine a writer used dry newspaper to recover different bullets in an experiment to test mushrooming. These were heavy hunting bullets, so to recover the tiny 55 grain bullet should be no challenge. Are your test bullets Nosler Partition, or some other premium bullet? If so, they should stay together to recover. By the way, this is the same weight bullet (or close) that the Washington sniper used. I doubt they were launched at 4100 fps though. The second best medium to use would be to line up several liberals. DO NOT AIM FOR THE HEAD! You would be putting your team in danger with the tiny bullets deflecting back! Then send me the bill. tongue.gif

[ 12-14-2002, 06:43 AM: Message edited by: stan v ]

mmd
12-14-2002, 08:21 AM
Not being a bullets and guns type of guy, I don't have any tangible expertise to offer, but the physics of the problem intriques me. The air tube idea sounds promising, but length and mechanical complexity of supplying enough air at the required volume and pressure might prove daunting. Tradjectory would be unpredictable in the turbulent airstream of an enclosed environment (ref. Bernoulli's work on flow in pipes), possibly causing the projectile to self-destruct against the airpipe walls.

Peter Malcolm's comment on the transitional densities problem offers the best hope for clean recovery, I think. I agree that to stop a projectile with minimal distortion to the projectile would require a gradual application of friction. Is it possible to obtain, or make, ballistic gelatins in varying densities and set them up in concert with other, less dense materials, to effect a gradual reduction in kinetic energy ? I envision a sequence of 1 cubic foot blocks of, say, light upholstery foam, dense upholstery foam, soft gelatin, medium gelatin, and finally firm gelatin.

Will you tell us your solution and the results when you're done?

stan v
12-14-2002, 11:07 AM
This test is being conducted to see exactly how a particular bullet behaves upon impact. Will the test be recorded with some super camera, John? I'd like to see that. The first foot of travel after impact would be an eye opener.

Ian G Wright
12-14-2002, 11:58 AM
Dead easy this one,,,,,,
Mount the rifle in a test vice, place the test vice and bench at the center of a shallow circular pond and set the rifle to fire EXACTLY vertically.
Wait for the splash and search underneath it.

IanW.

[ 12-14-2002, 12:00 PM: Message edited by: Ian G Wright ]

stan v
12-14-2002, 12:17 PM
That is an excellent idea! Maybe wars should be conducted that way, whoever gets hit on the head is out?

Peter Malcolm Jardine
12-14-2002, 12:20 PM
MMD, what liquids (or liquefied gases) offer less density than water, and can be contained in a suitable test environment for this experiment? I am thinking but not much is coming out :confused:

NormMessinger
12-14-2002, 12:20 PM
So far it looks as if Chris is the only one that has half a grip on this problem.

--Norm

Ian G Wright
12-14-2002, 12:44 PM
Originally posted by stan v:
whoever gets hit on the head is out?That works for me,,,,,,, better still the old coup stick system.
Human nature being what it is some twit would invent laser guided computor initiated sticks and fit out multi-billion $ first strike stick carriers. A constitutional lawyer would discover that citizens of the US had the right to bear sticks, the National Stick Assn would form to ensure that anti-stick laws should not be enacted. The burning of sticks would be outlawed. Right wing gangs would form to plant a National Stick Forest. Someone would invent light weight fiberglass sticks,,,,,,,,,,
Enough, I'm wandering again.
;)
IanW.

Shang
12-14-2002, 12:58 PM
"...A really long snow bank. But finding the round will be exceptionally tedious.
This actually works, BTW..." --Ross

Ross is right.
During my misspent youth we used to shoot our rifles at targets way to hell'n-gone across the snow. Waaaay down range, as often as not we find spent bullets, intact, laying on the surface of the snow.
With the muzzle velosity you mentioned I would suggest that Down-Range should be Canada.

Shang
12-14-2002, 01:05 PM
HEY! WAIT A MINUTE!
I just figured this out!

That stuff about the "Crime Lab" and the "55 grain bullet" is a cover-story!
John is designing the most hellish potato-gun the civilized world has ever seen!
At 4100 feet per second that Idaho sput should lift a PWC right out of the water!

John Gearing
12-14-2002, 01:43 PM
Alright guys, I'll fill in some of the data gaps I left in the first post. Just promise me you won't use this knowledge for evil. Seriously.

These rounds are a rare beast. If you ask for them (as I have) in typical gunshops or sporting goods stores you are likely to be told that they have not been made in some years. My specialist gunshop says that is not so and they were able to get me two boxes' worth in three working days. What you have is a .224" bullet weighing 55 gr sitting atop a .30-06 cartridge case. The bullet is copper jacketed to within about 1.5mm of the tip, which is softpoint (lead). The tail is simply squared off; no boattail. Instead of necking down the cartridge to fit the bullet, the bullet is encased in a plastic sabot that brings the diameter up to .30. Therefore, you can fire these in your regular .30-06 rifle just as you would any other -06 round. Made by Remington they go by the trade name ".30-06 Accelerator" for obvious reasons!

Upon exiting the muzzle the sabot peels away (according to some accounts within the first 14" of travel) leaving the bullet to fly to target alone. Of course this means that in theory the bullet should not exhibit any rifling striations since it did not contact the bore -- only the sabot did. There will be marks on the sabot but it is unclear as to whether they will allow the sabot to be matched to the barrel that fired it. We intend to test this hypothesis. And of course we would like to recover the bullet as intact as possible so that we can examine it for any markings it may have picked up. The potential forensic problem this round poses is clear. In terms of the DC sniper, for example, if he had been shooting these rounds from longer ranges and hides that allowed him to recover the spent sabots (data suggests they come to earth between 10 and 40 feet from muzzle) the authorities would not have been able to match the bullets to the gun. If they were really on top of their game, they might have deduced sabot rounds from the very lack of marks on the bullets, but then they would have to run around and try to find out who had been buying these rounds (and yes, independent manufacturers make sabots too, so one can handload rather than buy complete rounds from the manufacturer). But even if you knew who bought them, you still in theory wouldn't be able to match the bullets to the gun barrel that shot them.

The Connecticut State Crime Lab is a top-of-the-line outfit, being the home of the famous Dr. Henry Lee (gave a lot of testimony in the OJ trial---and is called in to consult on cases all over the US and around the world), and they've staffed it with a host of heavy hitters. Even so, none of them had ever laid their eyes on these rounds until I brought some in. Their opinion is that the bullet will turn to dust if fired point blank into their water tank. They have a 15 yard indoor range with a "snailshell" catcher, but they are not sure there would be much left after that little excursion either. Since posting this last night I have been in touch with Mr. Leslie Dukes in Georgia, who has developed a forensic bullet trap that seems almost too good to be true. He is also of the opinion that if launched into water my rounds will turn to dust. But he is absolute in his belief that his system will catch the bullet not only intact, but pristine. See it at www.ballisticsresearch.com (http://www.ballisticsresearch.com)

If this thing does what he says it does, bullet ID as a part of forensic science just got a lot easier. Mr. Dukes is willing to bring his system up here for a demonstration and to test my rounds, and I plan on discussing this with the crime lab on Monday.

Thank you all for your advice. Yes, I agree, the medium either must be very light (like snow) or of graduated density. One way might be to use a trough filled with snow having graduated water content: very dry snow for the first few feet, then slightly wetter, then wetter still, and finally something like slush at the end. But from a practical standpoint I suppose the problem would be how to create these specific snows!!

stan v
12-14-2002, 02:32 PM
So, liberals are out of the question?

mmd
12-14-2002, 02:37 PM
Peter Malcolm: Most of the liquids that are less dense than water that come to mind have the disconcerting property of being somewhat reactionary to heat and pressure. To whit:

Dumb: "I got just the stuff for your ballistics test. It's specific gravity is only 72% that of water!. I got the test tank all ready to fire."

Dumber: "Yee-haw! Let's go shootin'!"

BANG!

BOOM!!

Dumber (on the way up): "What was that stuff?!!"

Dumb (on the way down): "Gasoline. Why?"

Ross Faneuf
12-14-2002, 03:04 PM
Interesting to read that their energy-dissipating material is, in fact, much lighter than snow.

htom
12-14-2002, 03:05 PM
I've seen the snowbank thing in operation, too. Finding a particular round would be more than hard. I was going to suggest shooting into a foam of some sort, a very long trough filled with some kind of gelatin-foam.

Your linkee seems to be working on a different (and even better) scheme; he's wrapping the bullet and using the enlarging diameter as a means of protecting the bullet while slowing it. Neat.

Not neat -- over the years, there have been murder stories wherein the bad guy used a sabot to fire a bullet that falsely labeled someone else's gun as the murder weapon. Good tales, some of them, but not possible in real life because you couldn't do that. Now, it seems, you can.

John Gearing
12-14-2002, 04:43 PM
Yep, Accelerators were also produced in 30-30 and .308......

jack grebe
12-14-2002, 06:33 PM
sooo........what your saying here is that it IS
possible to shoot a .222 round from say a 7mm mag
without modifing the rifle? :confused: if thats the case those deer don't have a chance next year :D

George Roberts
12-15-2002, 01:27 AM
I don't do bullet research but ...

shooting outside thru snow is a bad idea. You are unable to show the bullet found was the bullet shot.

There are several good mediums for stopping fragile high speed projectiles. If you have a legal purpose for doing so, you should know what they are.

John Gearing
12-16-2002, 02:52 PM
Mr. Roberts--
I trust that you did not mean to infer that since I do not know of a method of catching these bullets intact, my purpose for knowing same must be illegal?

edsr
12-16-2002, 05:20 PM
John,
Have you considered reducing the temperature of the bullet? As I understand it, temperature can greatly affect the velocity. Perhaps the ammo maker would have some info on the temp. v.s.velocity.

I actually have a box of .22/30'06 rounds that have been sitting around for year and I hve never used. Let me know if they would help in your research.
edsr

Shang
12-16-2002, 07:30 PM
"...During my misspent youth we used to shoot our rifles at targets way to hell'n-gone across the snow..."

A'right, a'right! We were poaching penguins...

George Roberts
12-16-2002, 07:41 PM
John ---

1) You are working with professionals who do this for a living and you need to ask us for an solution.

2) A solution, if one exists, will do no good for comparision purposes because any bullet shot normally will be destroyed.

----

While I can think of no legal useful purpose, I can also think of no illegal useful purpose.

Mrleft8
12-16-2002, 11:32 PM
Light fluffy snow, gradually turning into heavy slushy snow? I know the perfect place! I-91 from about Enfield down to Wallingford or Hamden! :D

John Bell
12-16-2002, 11:55 PM
Dang if I know the answer to this question, but I'd sure love to be around when you test your various hypotheses. Thanks for the interesting discussion, y'all. Don't let the naysayers get you down.

rodcross
12-17-2002, 12:56 AM
Sorry about the others. They don't understand that knowledge is the key to understanding.

Learn everything you can about the bullet!

I have not given up on Silly Putty.

Doubters Abound!

Shang
12-17-2002, 03:03 AM
"...I have not given up on Silly Putty..." --rodcross

...shot from a potato gun...
...Yeah! I like it...!

skuthorp
12-17-2002, 03:31 AM
How about a tank full of sewage? You could make the slurry to the consistency required, it's cheap and seems somehow appropriate!

stan v
12-17-2002, 07:18 AM
John, here's a link on one of my handloading sites that discusses 30-06 sabots. Hit the "next" button to see each in order.......

http://pub12.bravenet.com/forum/fetch.php?id=9884886&usernum=1029604416

LeeG
12-17-2002, 08:01 AM
JohnG,,wow,fun thread,,I was conjuring up all kinds of densities of aerogel but that sounds pricey,,,oh about mr. G.Roberts he likes to leave dangling implications and condemnations as a staple of communication, you'll get a clear sense of where he's coming from,,er and not.

Ian McColgin
12-17-2002, 09:15 AM
Perhaps if you had a good baloonist and a very good marksman, you could float the baloon at the height you calculate as the top of the trajectory. Marksman fires pretty much up. Fellow in the baloon catches the bullet at the moment of no velocity. (Don't forget to allow for earth's rotation.)

Ian G Wright
12-17-2002, 10:22 AM
There was a case of murder here in the UK (gun capitol of the world) in the 1950's. The murderer, to avoid (he thought) any forensic link 'twixt gun and ammo cast a solid slug of dry ice, CO2, and shot the victim from close range with a 12 bore(no choke).
They got him anyway, half a dozen people saw him do it,,,,,,

IanW

John Gearing
12-17-2002, 11:50 AM
George,
Yep, I need to ask the forumites for possible solutions because the professionals don't have one! Water tanks are the standard tool used for bullet capture but they won't work with frangible or extreme velocity rounds. Because of the special construction of this round, neither the firearms experts at the crime lab, nor my gunsmith, nor a noted area handloader were able to disassemble a round (so as to permit replacing the powder charge with a reduced charge amenable with the water tank) without destroying one of the key components of the system (the sabot). What we could have done had we had more time is to buy the necessary dies and some loose sabots and bullets and create our own reduced-power loads from scratch. But, our schedule was too tight to allow us to go this route. Therefore, I was considering bullet capture alternatives that I might pursue on my own. And what more creative, supportive folks could I have tapped into for advice than the fine community of friends right here on the forum? I am continually amazed at the incredible depth and breadth of skills folks here have, and their willingness to share their knowledge. :D

John Gearing
12-17-2002, 11:59 AM
Lee G--
Aerogel?? Wow, that brings back memories! It's been a few years since I've seen any -- my wife had some in a little display case on her desk at Lockheed. Very cool stuff. To change the subject a little, we used to use something I can only describe as "aluminum foam" as a gas-permeable plug for solid propellant rocket motor nozzle openings. The word was that there was only one source for this stuff -- a guy who ran a one-man operation making it in his garage or something. Supposedly we had sunk a couple million bucks into research to figure out how to make it ourselves (to the best of my knowledge, there were no intellectual property issues) but had no success at all. Materials---there's some amazing stuff out there!

cs
12-17-2002, 12:28 PM
I think that Ironmule touched on the solution. Distance. Set up the weapon on a tri-pod on a long distance range and fire into a water tank. Maybe with enough distance and an accurate shooter you could recover the round with minimal damage.

Chad

thechemist
12-17-2002, 03:09 PM
Drill a very small hole in the side of the cartridge case.

Using a hypodermic and a fine needle and a microliter syringe, inject various small amounts of water into the cartridge.

Use soapy water so it wets the powder grains.

Shake well before use.

The dampened powder should burn more slowly and the grain-to-grain combustion speed be also reduced, and with enough water the muzzle velocity should be reduced enough that you can have a low-velocity bullet to catch in a conventional manner.

For a standard 30-06 cartridge case stuffed full of powder [probably 40 grains or so.....my own 30-06 Improved takes about sixty grains of 4831.......] I would estimate the order of magnitude of water that might be used to be fifty to five hundred microliters.

It may be that water alone will not form a surface film on the powder grains sufficient to slow down combustion propagation enough, in which case try a water/propylene glycol mix. A water/sodium silicate solution may also be effective.

The cartridge case will likely split on the side when fired, but you should be able to get the spent casing out, even if you have to remove the bolt and insert a ramrod.

Nicholas Carey
12-18-2002, 02:54 AM
Originally posted by John Gearing:
Okay gang, here's the deal: I need to shoot a special high velocity round into something that will let me retrieve the bullet at least somewhat intact. Here are the specs: it will be a 55 grain bullet traveling at close to 4100 feet per second. The good folks at the State Crime Lab, with whom I'm working on this project, figure that if they shoot into their water tank (as they would normally do) all we'll get back is "dust", and on the basis of an independent expert I've been talking with, I agree with them...One of my thoughts was to build a tube full of ballistic gelatin (with overflow ports every so often) and fire into that. Any other thoughts???One of the 'old' way to do what you want to do is build what I'm going to call a 'baffle box' to trap the round and fire the round into that.

one-inch clear white pine (or similar) boards spaced a couple of inches apart. The pine baffles slow the round down and the spaces provides space to jettison wood waste.

I've got no idea how well it would actually work, but it's an idea.

Nicholas Carey
12-18-2002, 03:03 AM
One other thought -- fairly soft two-part foam, as used for crating artwork, floatation, etc. Fill up a box with it (of sufficient depth -- your call as to what that is).

The foam is mostly air, so it shouldn't do too much damage to the bullet, I wouldn't think. But terminal ballistics is a tricky place.

Another note re: sabot rounds -- Dynamit-Nobel makes a .50 caliber sabot slug for a 12-gauge shotgun. Supposed to provided superior performance when deer hunting with a shotgun.

Ron Williamson
12-18-2002, 06:29 AM
Why wouldn't you ask a manufacturer to make some reduced load rounds?
R

sck1
12-18-2002, 08:00 AM
You could cut the back off of one, (tubing cutter should do it without heat buildup) empty the casing and take it to a machinist to grind it away from the sabot. If he knows what he's doing you can get the woking end out with no damage, or at least none that will alter the results of your test. Then you can yank the bullet out of another casing and make a nice slow load to test with.
Steve

rodcross
12-18-2002, 09:03 AM
Wouldn't a slow load defeat the purpose of the test? If the purpose of the test is to find a unique signature for each weapon, you already have part of the problem solved if you have the shell casing; more of the problem solved with the sabot, and a slug with NO rifle marks would lead you to concentrate on the first two items. A soft piece of metal being shoved out of a barrel at that velocity may show some subtle, identifiable deformations unrelated to the barrel, that might be different if a slow load were used.

John Gearing
12-18-2002, 01:29 PM
One of the problems with "solid" bullet catchers, such as foam, or cotton waste is that at the velocities we're talking about the material is quite abrasive to the bullet surface and usually removes too many marks to make for a reliable identification. Another problem is that if the material is flammable a hot bullet can ignite it.

We could have asked Remington to make some downloads for us, but there are two problems with this: 1) the time factor--our schedule is tight, and 2) I don't think the experts at the lab who would be firing the shot would trust that the rounds were really downloaded unless they themselves had seen it done. Since one of their concerns was safety, I think they would be hesitant to trust even Remington to get them the right stuff.

Even if we cut open a shell and milled away the sabot, we'd still need to get some specialized tooling to reseat the sabot and bullet properly. Again, time becomes the factor.

I suppose it is possible that there could be some deformation on the bullet at full power that would not be present at reduced velocity, but that is a risk we would have had to take, since there is no way to capture one of these full power bullets intact.

Yes, the shotgun sabots are quite accurate and effective. When they were first introduced and Mossberg produced a shotgun with a rifled barrel, one of the gun mags tested the combination and shot a sub-MOA 3 group shot at 100 yds. Impressive.

rodcross
12-18-2002, 02:25 PM
Silly putty.

Ah, well, nobody listens to me, anyway.

cs
12-18-2002, 02:36 PM
I still think the answer is distance between the gun and the recovery tank.

Maybe we can set up a recovery tank with silly putty at a range of say 800 meters.

Chad

thechemist
12-18-2002, 02:45 PM
rodcross:

You know, that's a good point. I wonder how much pressure has built up by the high-density air in the remaining length of the barrel being compressed by the Mach 4 bullet in the remaining part of the barrel.....?

Actually, that is amenable to calculation. Since the bullet is going at faster than the speed of sound, which is Mach One, essentially all the air in the barrel will be compressed into a small wad in front of the bullet, until it gets to within a few diameters of the muzzle.

For a [for example] thirty-inch barrel, that is on the order of fifty diameters in length, and one would expect thus at most fifty atmospheres pressure in front of the bullet, or 750 psi. That should not distort the bullet or sabot much, I would think.

[ 12-18-2002, 02:46 PM: Message edited by: thechemist ]

rodcross
12-18-2002, 03:12 PM
Huh?

Um.....

Right! Right! My thoughts exactly.

It is amazing stuff, however. It shatters when you hit it with a hammer; Bounces like a super ball and yet is soft and pliable, like clay. It wouldn't work for John's project if it had any abrasive mineral content. I haven't a clue what its made of.

Shang
12-18-2002, 04:17 PM
Okay, you didn't like my snow-field idea, so let's try carrying Ian's suggestion one step further...

You t fire the rifle straight up...
...at the zenith of the bullet's path it's speed is reduced to zero...
...your assistant, waiting in a hovering balloon, reaches out and catches it!

(Note: it may be necessary to have several assistants and several spare balloons in order to get the range exactly right.)

Nicholas Carey
12-18-2002, 09:45 PM
Originally posted by cs:
I still think the answer is distance between the gun and the recovery tank.

Maybe we can set up a recovery tank with silly putty at a range of say 800 meters.I think you're onto something WRT to distance being the key -- I'm dubious about the silly putty though.

I dug up Remington's published ballistics on this round and this .30-06 sabot at 500 yards is looking a lot like a Remington .223 loaded with the same 55 grain pointed soft nose out somewhere around 300 to 400 yards.

So I say, beg, borrow or steal a 1,000 yard range somewhere (and a good bench rest shooter with his .30-06 tool of choice), set up your bench rest and go for it. I'm not sure I'd go out further than 500 yards though. That tiny little bullet looks to be dropping pretty fast at that point.

Here's the Remington's published data on the ballistics of these two rounds:

</font><blockquote>code:</font><hr /><pre style="font-size:x-small; font-family: fixed;">Remington .30-06 Accelerator Ballistics
Factory Load, #9-1/2 primer
---------------------------------------
Range Velocity Energy Trajectory
(yards) (ft/sec) (ft/lbs) (inches)
------- -------- -------- -----------
Muzzle 4,080 2,033 + 1.4
100 3,484 1,482 + 1.4
200 2,964 1,073 0
300 2,499 763 - 2.6
400 2,080 528 -12.2
500 1,706 355 -30.0

.223 Remington Ballistics
Factory Load, #7-1/2 primer
---------------------------------------
Range Velocity Energy Trajectory
(yards) (ft/sec) (ft/lbs) (inches)
------- -------- -------- -----------
Muzzle 3,240 1,282 + 1.6
100 2,747 921 0
200 2,304 648 - 3.1
300 1,905 443 - 8.2
400 1,554 295 -26.2
500 1,270 197 -58.6</pre>[/QUOTE]

Nicholas Carey
12-18-2002, 09:49 PM
Originally posted by rodcross:
[Silly Putty] is amazing stuff, however. It shatters when you hit it with a hammer; Bounces like a super ball and yet is soft and pliable, like clay. It wouldn't work for John's project if it had any abrasive mineral content. I haven't a clue what its made of.According to the Silly Putty web site (http://www.sillyputty.com/) -- you knew there had to be one :D -- Silly Putty was originally made by mixing silicone oil with boric acid. Another serindipitous invention -- he was trying for synthetic rubber.

However, these days, it's been improved. From about.com's web page on Silly Putty:


Composition of Silly Putty
65% - Dimethyl Siloxane
17% - Silica
9% - Thixotrol ST
4% - Polydimethylsiloxane
1% - Decamethyl cyclopentasiloxane
1% - Glycerine
1% - Titanium Dioxide

[ 12-18-2002, 09:51 PM: Message edited by: Nicholas Carey ]

rodcross
12-19-2002, 05:10 PM
17% Silica. Bummer! Abrasive!

Nicholas Carey
12-19-2002, 06:58 PM
Originally posted by rodcross:
17% Silica. Bummer! Abrasive!Silicone oil + boric acid was the original recipe, right? Hmmm...googling....

Silicone Oil (http://www.chemistrystore.com/Silicone_oil.htm) seems to be $25/gallon.

Boric Acid (http://www.chemistrystore.com/boric_acid.htm)...less than $1.75/pound.

A little work in the lab and we have it.

[ 12-19-2002, 07:04 PM: Message edited by: Nicholas Carey ]

George Roberts
06-29-2005, 10:06 AM
John Gearing ---

Real simple solution ....

High speed photo.

This method has been used before.

gary porter
06-29-2005, 02:24 PM
Originally posted by cs:
I think that Ironmule touched on the solution. Distance. Set up the weapon on a tri-pod on a long distance range and fire into a water tank. Maybe with enough distance and an accurate shooter you could recover the round with minimal damage.

ChadYou can also locate an old Winchester emi-automatic
in 30-06, can't remember the model and I think they have managed to outlaw them most places now but someone should have one. This rifle will not have the same muzzle velocity due to the recoil I think. Anyway what Chad says will work, you can also shoot through some matresses to slow it down first.
Gary

Gary E
06-29-2005, 06:08 PM
So who is bumping off who? ifin its the mob why does anyone care?

Just a thought on this sabot bullit...isnt the idea that the bullit never contacts the rifle barrel? so what marks do you expect to find on it?

As a kid one of our gun nut friends took a .270 case, necked it to .17 and could drill holes in dimes stuck in a fence post on the other side of the lake. Why I dont know, mabe the woodchucks were pests.

seafox
06-29-2005, 08:20 PM
taking the tray idea I wonder about filling it with sean wrap handing over dowells say 1/4th inch diamiter and thus the plastic would have a bit of give and be able to move out of the way

Bob Cleek
06-30-2005, 12:43 AM
Maybe a dumb observation, since a bunch of people here seem to know what they are talking about, but anyway, what about ballistic putty? Isn't that what it's made for?

mbogo
06-30-2005, 10:24 AM
The problem with this is that the Accelerator rounds were loaded with varmint bullets - intentionally light construction to allow them to blow up on impact for maximum damage and minimum ricochet danger. They are very different from the NATO standard bullets, or even the heavier .224 bullets avilable now that ARE suitable for deer-sized game.

Trying to capture these projectiles in any sort of medium is very difficult, even at the more sedate velocities in typical .223 or .222 cartridges. You end up picking 20+ little chips and fragments out of your gelatin with tweezers. Take a look around the web for some ballistic gel test results.

Velocity is the culprit. Accuracy of these rounds will not permit long range shooting to reduce impact velocity. In my experience, there is no way you could reliably hit a square of ballistic gelatin at 300 yds, let alone 500 yds, and even if you could, they would still blow up. That's what the bullets are designed to do.

The only way to test this is to load your own. Get some sabots, tougher bullets than the factory loads (as the intent here is to have the bullet stay together), and some low velocity loads that you can fire at short range and still hit your target. The sabots themselves I have found anywhere from 20 to 80 feet from the muzzle (at full power velocities in my .308). Lots of luck...

paladin
06-30-2005, 10:49 AM
Oh crap! Calculate the range and distance to get the bullet subsonic, Fire a few rounds for effect and impact zone.....make a very large table...several folding leg tables....and stack multiple heavy ply trash bags up filled with water..the bullet(s) will be rcovered when the water drains from the punctured bag(s).....have done this with .17-223......

[ 06-30-2005, 11:03 AM: Message edited by: paladin ]

htom
06-30-2005, 11:53 AM
Dig a pit 100' in diameter. In the center construct a centrifuge with an 80' arm; mount the rifle on an end of the arm and balance. Line the walls with ballistic gel, reduce the air pressure to nearly zero, spin up to 1000 rpm (butt of the rifle first), and pull the trigger.

The rifle is traveling at about 4100 fps and the bullet emerges at approximately zero fps and is easily caught by the gel. Maybe a 75' arm.

paladin
06-30-2005, 12:19 PM
trash bags izz easier 'n cheeeper....

P.I. Stazzer-Newt
06-30-2005, 12:20 PM
htom :D
Neat and you get a 5000G centrifuge.

Ken Hutchins
06-30-2005, 09:58 PM
Of course you came to the right place, we are wooden boat people. To make wooden boats a by-product is saw dust, a perfect bullet stopper. That bullet will go thru between about 3 to 4 feet of dry sawdust. Make a box maybe 4 to 5 feet long out of plywood, except for the entrance end, use cereal box cardboard for that end, fill the box with saw dust with paper dividers about every 6 inches to help locate the bullet. The length of travel in the sawdust will be about the same for similar energy levels of other bullets. If the bullet exits the back of the box and I doubt if it will, just dampen the saw dust, really damp and the bullet will stop in about 2 feet. Been there, done that. smile.gif

blacksmith
07-01-2005, 06:34 PM
The 220 Swift was advertised at 4110 FPS muzzle velocity but with a 48gr bullet.Don't the balistics labs use something like a bale of cotton to arrest bullets?