School Science Project

[Combat-wombat]

I'm doing a school science project which involves testing the expansion of different types of JHP bullets. I have to do 3 tests for each brand of ammunition, and I'm testing three brands. How should I test this? I hear pre-made ballistic gelatin is quite expensive, and it's hard to make yourself. Would the water-filled milk carton test work? I just need an economical way to test 9 bullets.
Also: what particular brands should I test to get the most reliable mushrooming? I'm thinking Federal Hydra-Shok, Speer Gold Dot, and something else, maybe Winchester Ranger-Ts. Tell me your ideas.

Thanks.

 

[Phantom Warrior]

My best friend tested expansion using a garbage can full of water. A couple of them did look like they had whacked the bottom despite all the water they had gone through. You might want something a little bigger than a milk carton. Just a thought...

 

[Hedger]

Wet Stuff

Try a stack of wet newspapers or phone books (shoot at them end on). This will also make it easier to retrieve the bullets for inspection afterwards. Its not perfect, but its a school science project, right?

 

[Kodiak AK]

Use a 55 gal drum if you can find one . If not try a 30 gal trash can. If not that , you can do it with a 5 gal bucket , but you need to stand back a bit and realise what ever you use will probably be useless for holding water again.

 

[Archie]

Couple of ideas.

What ever you use, it has to be the same for all the tests. No since in comparing Silvertips shot into hogfat with Hydra Shoks shot into playground sand.

Water, milk jugs (the plastic kind) and newspaper are readily obtainable. I've used several milk jugs filled with water in a row, fronted by one inch of newspaper. The problem with this mechanism is one doesn't always find all the bullets.

If I were to start this again, I would make a plywood trough or tunnel about as long as I could make it. (Eight feet, I guess.) Leave one end open and make it so one side or the top is removable. Then use water filled milk cartons or newpaper or wet newspaper as the stopper material. Trouble with newspaper is how to pack it in uniformly for all nine tests.

If one has access to a meat cutting plant or slaughter house, one might investigate getting bulk fat or somesuch. It is in fact "tissue". The problem with fat is that it goes bad and smells like something dead in a short period of time. If I had a range, I would not appreciate the trash cans filled with spoiling fat.

 

[Waitone]

Wet phone books. Use something like box sealing tape to hold it together.

 

[Sisco]

What caliber are you using? When I tested expansion on .41 mag loads I used milk jugs full of sand. Discovered it took four of them when shot from ten yards or so to be able to recover the slug.
Since you're using factory ammo you should be able to find the rated velocity on the manufacturer's web site. A chronograph would be great to have for recording actual velocity though.
Along with expansion you could demonstrate penetration by using phone books, Sears catalogs etc and check the number of pages it went through. Or, fasten 2x4's or 2x6's together and measure the depth of the hole.
I wanted to do all this for my son's science project but his teacher rejected the idea. Imagine that.

 

[jsalcedo]

You can buy powdered carageenan and make up a big batch of gelatin.

Then you can fill 3 mil contractor grade trashbags with a measured amount and use them for your test.

The carageenan is bio degradable and reusable for at least 3 or 4 days.

 

[Renegade]

The bad thing about using sand, is depending on much sand the bullet travels through there isn't much of the bullet left. I wanted to show my son what a bullet would look like after being shot. I used a plastic canister filled with wet sand and placed a lid on the canister. Placed the container length wise and fired a round into the lid of the canister. When I recovered the bullet there wasn't much left, mainly jacket material and very little of the lead core, and this was a 165gr bullet fired from a 30-06 at 50yds. Sand will stop a bullet, but you won't get what you're looking for.

Later,

Dave

 

[TechBrute]

Just use ballistic Jello. I hear that cherry is the most realistic because it looks like blood.

 

[Combat-wombat]

Well, how could I easily and cheaply get that ballistic jello?

 

[TechBrute]

I think it's like $.80 per package at the grocery store.

 

[Combat-wombat]

So just a large amount of regular gelatin would work? About how much would stop the bullet? I'm not sure what caliber we will be using, but say from a .357 magnum fired out of a 2.5 inch barrel?

 

[TechBrute]

Sorry dude, I'm just joking around. If there's a way to stop bullets with Jello, I sure don't know how.

 

[Azrael256]

Anybody you know have a swimming pool? A good 8 feet of water will stop just about anything. Oh, but don't try it with anything labled "Mauser" or "Luger." Those bullets will just stop at the surface.

 

[twoblink]

The wet phonebook approach is the best.

Why?

It's very cool to say (Brand X reached the "Johnsons" while Brand Y reached the "Smiths")

The other method is coke cans with sand...

We did "poor man's ballistic testing" in Vegas with the phone book method..

 

[Andrew Wyatt]

when i did this science project, i used one brand of .22 RF ammo and shot it out of four different barrel lengths, and chronoed it while i was shooting. I used pottery clay, and packed it into welding rod containers.

 

[HankB]

You could build a long wooden framework which would hold a series of water-filled, gallon-sized Ziploc bags. Shooting into the end you'd have a consistent, repeatable medium AND a measure of how deeply the bullets would penetrate.

IIRC I read somewhere that the expansion results of this method were consistent with ballistic gelatin, but the bullets penetrated somewhat deeper.

Neat that your school doesn't have a "zero tolerance" policy that will get you expelled for even MENTIONING the words "gun" or "bullet."

 

[Snowdog]

Make your own play dough. It doesn’t make a mess and will give you picture-perfect expansion every time. It's also biodegradable, so once you're done, toss it out.

I've been using the same generic play dough (that I bought at Wallyworld) for over 5 years now, having done a couple hundred tests of various JHPs.
I guess testing JHPs in play dough could be considered one of my hobbies.
I've kept this play dough viable by keeping it in a 5 gallon pail, careful to tuck a trash bag around the play dough and to keep the lid sealed on after each use.

I typically make four 6" cubes and line them back to back in a line. This is plenty enough to stop any JHP up to a .44mag from a Marlin 1894.

24†of play dough was enough to stop this 250gr Winchester Partition Gold .44mag JHP from a Marlin 1894

However, I would still suggest larger blocks if possible to allow more room for error. Also be sure to have a safe backstop behind the playdough should a JHP fail to open and cut through the last block. I've never had this happen, but I'm sure it can with Murphy around.

Be sure to wrap the first block with a trash bag during the test, as it will usually explode without one after struck by a JHP of 9mm or larger. The others behind it usually stick together.

I'm not sure how to make play dough, but others here might. If you do a search here for play dough, you'll find the recipe (and many of my posts, I'm sure).

It's great to work with. You shoot it, follow the "wound track" to the bullet, dig it out, rinse the expanded bullet with water and reshape the playdough for another shoot... so simple and easy, you might find yourself doing it for fun after your project.

Good luck with your science project.

Play dough loves bullets (recently tested 120gr 9x18 SilverBears on 5+ year old play dough)

 

[Justin]

The one time I ever messed around with testing hollowpoint expansion, I just used milk jugs filled with water, lined up end-to-end. IIRC, it took something like seven or eight milk jugs in order to have enough resistance to make a round recoverable.

To do three tests with multiple brands of hollowpoint...that's a lot of milk jugs.


Also, just in case you're interested in trying the ballistic gelatin route, here's a link to a recipe and info on proper testing.

http://www.recguns.com/Sources/XD3.html

 

[Snowdog]

I figured I'd look up the recipe rather than be lazy and tell you to do it.

Here's the general play dough recipe from http://www.teachnet.com/lesson/art/playdoughrecipes/traditional.html .


Traditional Play Dough
• 1 cup flour
• 1 cup warm water
• 2 teaspoons cream of tartar
• 1 teaspoon oil
• 1/4 cup salt
• food coloring
Mix all ingredients, adding food coloring last. Stir over medium heat until smooth. Remove from pan and knead until blended smooth. Place in plastic bag or airtight container when cooled. Will last for a long time.

 

[NavajoNPaleFace]

Snowdog, thanks so much for that play dough recipe.

I've been looking for something like that for ages.

Whooooo hoooooooooo!

 

[benEzra]

What you need is a "Fackler box"--a long trough that you can fill with water-filled Ziploc bags. Penetration can be measured by which bag the projectile stops in.

Anybody have a link to how to build one? (Looks like SWAT magazine, Feb. '02, had an article.)

 

[BluesBear]

Actually 10% Ballistic gelatin isn't that hard to make.

http://www.recguns.com/Sources/XD3.html
http://www.vyse.com/gelatin_for_ballistic_testing.htm
http://www.firearmstactical.com/tacticalbriefs/volume3/number2/article1.htm

Now for the EASIEST way.

Knox Gelatin available at almost every large grocery store mixed 4 parts Gel to 1 part water works almost as well as the fancy stuff.

Just make a very large batch so it's all exactly the same.
Place a small plastic grocery bag inside a .50cal ammo can for a mold.

 

[Treylis]

School science project?

I see you're in the PRK... won't your teacher/professor freak out and label you a terrorist/militia nut/call security on you because you're obviously going to shoot up your school because you did a project involving guns in any way?

I imagine that would really cause people to go nuts even here in Arizona... your project sounds interesting but I'm just wondering what kind of reactions you're getting/planning to get.