Exploding BB pellet

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Infernal Maveric
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Sun Sep 09, 2007 11:24 am

Today I decided to modify my QB gun, to have a way smaller chamber and pilot. I then went a pumped the baby up to 375PSI and let rip at a box full of my little sisters toys.
The BB entered the cardboard box, but met a dead stop at a plastic Barbie tray. This caused the BB to explode into about 12 pieces, varying in sizes.

Is this because of the dramatic stop the pellet came to, or was it just a faulty BB (BTW I'm using pro BB's from eBay, the type that have no seams ect) ?
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hi
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Sun Sep 09, 2007 11:33 am

it probably exploded because of rapid de-acceleration. another thing is it was plastic, which by the way isnt the strongest material in the world.
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jackssmirkingrevenge
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Sun Sep 09, 2007 11:35 am

A high velocity impact will shatter a BB when striking hard objects, ironically I just did this myself with my
6mm burst disc launcher:

[youtube][/youtube]

here's what was left:
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DSCF0992.JPG
hectmarr wrote:You have to make many weapons, because this field is long and short life
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Infernal Maveric
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Sun Sep 09, 2007 11:43 am

Ahh ok, fair enough then. Just wanted to make sure the BBs I have are fine. Ill get some pictures of my modded gun and damage shots up when I find my DC-cam.
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frankrede
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Sun Sep 09, 2007 3:25 pm

Infernal Maveric wrote:Today I decided to modify my QB gun, to have a way smaller chamber and pilot. I then went a pumped the baby up to 375PSI and let rip at a box full of my little sisters toys.
The BB entered the cardboard box, but met a dead stop at a plastic Barbie tray. This caused the BB to explode into about 12 pieces, varying in sizes.

Is this because of the dramatic stop the pellet came to, or was it just a faulty BB (BTW I'm using pro BB's from eBay, the type that have no seams ect) ?
What happens when you drop an object on the floor? It breaks.
Current project: Afghanistan deployment
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windshrike
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Sun Sep 09, 2007 3:27 pm

Well, with Jack's gun, it very well might break because of the stresses from breaking the sound barrier(assuming by some fluke it does do that).
But frankrede is right.
Last edited by windshrike on Sun Sep 09, 2007 3:31 pm, edited 1 time in total.
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Infernal Maveric
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Sun Sep 09, 2007 3:28 pm

I didn't shoot a vase out of my gun, I shot a BB which don't shatter under usual circumstances.
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windshrike
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Sun Sep 09, 2007 3:33 pm

But at a very high velocity with a far more rapid deceleration, causing untold stresses throughout it. And at 375 psi it would have been going wicked fast.
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singularity
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Sun Sep 09, 2007 5:29 pm

i have had "high end" bbs shatter when i use them in my vortex gun, the plastic they make most of them out of seems to be very brittle (put one in a pair of pliers if yours are like mine the shatter sending little plastic fragments everywhere instead of deforming) my vortex gun its only running in the 80-120psi range with your gun running 375psi its not surprising they broke.
be sure to check out my <a href="http://www.spudfiles.com/forums/ak-styl ... 9.html">AK Styled Vortex Gun</a> and my <a href="http://www.spudfiles.com/forums/at-4-t9627.html">AT-4 Rocket</a>

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th3p0p0
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Sun Sep 09, 2007 9:19 pm

i shoot KSC bbs out of my aeg and there is no better bbs out there and i break them all the time but my gun is shooting at 400 fps with a .20 at 800rpm lol :lol:
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blind909
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Sun Sep 09, 2007 9:57 pm

i sometimes use those cheep blue bbs, they look like the ones u have in da pic, and they shatter all the time its normal.
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Rudesill Ballistics
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Wed Sep 12, 2007 4:04 am

When you said BB I was thinking you destroyed a Copperhead or something.

I was just gonna say WOW!

But disintegrating a solid plastic sphere is quite a feat too...

This is why some rifle bullets explode, rapid deceleration causes the material to break apart.
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Redcoat
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Wed Sep 12, 2007 4:15 am

Look, if i can shoot out of a 27 dollar AAA battery Tokyo Marui Glock 18c (It's Awesome) and shatter bb's at a range of 5m i think that's what you would be experiencing.
Infernal Maveric wrote: I then went a pumped the baby up to 375PSI and let rip at a box full of my little sisters toys.
That's just plain mean. :angryfire: You is a bully. :evil:

Happy SPuddin'
Poo.
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jackssmirkingrevenge
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Wed Sep 12, 2007 4:54 am

Rudesill Ballistics wrote: This is why some rifle bullets explode, rapid deceleration causes the material to break apart.
Image

This doesn't happen due to deceleration, what occurs is that the bullet starts to tumble (because flesh is denser than air and the gyroscopic stability imparted by the rifling is lost) that results in centrifugal forces too great for the construction of bullet to withstand so it flies apart.
When you said BB I was thinking you destroyed a Copperhead or something
The steel that BBs are made of is relatively soft, it will flatten visibly if fired against a hard target such as steel plate.
hectmarr wrote:You have to make many weapons, because this field is long and short life
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