[bobgengeskahn]

I have been working on a few different ideas about gun design etc. and have gone back to the drawing board with the actual design of the BB. One thought that occurred to me was the method by which shot is made for shotgun shells (here is an article):
http://en.wikipedia.org/wiki/Shot_tower

Basically molten lead is dripped through a tower, where the aerodynamics of falling creates a sphere and hardens on the way down. Once at the bottom it is rapidly cooled by hitting a body of water.

 

[brickerenator]

This could be a sweet idea. I wonder how far molten bb's would have to drop.

Your biggest hurdle would be to get the bb's to form the correct size.

http://projects.nfstc.org/firearms/module05/fir_m05_t05_03.htm

The lead flowed into a broad shallow pan with fine holes in the bottom.
A device struck this pan several times a second.
Molten lead flowed as streams from holes in the stationary pan; vibration from the impact broke the streams into droplets of random size.

Doesn't seem like it's an exact science...

 

[becklr1]

Here is how it is typically done today for contrast.

Not sure shot balls are any more precise than bb's and the size varies more I suspect? Just guessing though.

 

[bobgengeskahn]

Here is how it is typically done today for contrast.

Not sure shot balls are any more precise than bb's and the size varies more I suspect? Just guessing though.

As far as varying size, I would imagine that if you had a known substance with a known density when cool and a known expansion at certain temperatures you could measure the amount that is dropped at a time and ensure proper size. Ideally the cooling combined with the motion would also create a uniform density. Finally you could always put them through a polishing machine and add some uniformity and smooth out the surface.

The advantage to something like this, I would imagine would be two fold:
1. You would have a uniform density, ensuring even hop rotation.
2. There would be no mold release to deal with or clean off the BBs when you buy them.

 

[becklr1]

I suspect plastic wold cool before becoming round. I think it would cool too quick prior to becoming perfectly round. Just a guess though. Plastic cools quick relative to metal if I recall. To lazy to look up material science but worth looking into.

 

[inthetallgrass]

Hitting the water would deform thee shape slightingly thus ruining th bb. You'd want a metal which would harden about half-way down the liquid so it could form a perfect sphere again.

 

[lainthecity]

Simple, you make plastic bbs like a BB gun pellet.
Then shoot it at high velocity, which gets rid of the hop up.
Fragmentation for energy dissipation.
(Don't hate! Its just a brainstorming idea! Shoot it down with whatever you got!)

 

[bobgengeskahn]

Mmmmmmmm... when I think of fragmentation rounds I think of glasers, and when I think of glasers I cringe. In all of the inspiring theoretical discussion that has been going on recently, I think we need to remember that whatever comes of it, our ideas should be playable lol.

 

[becklr1]

I am not so sure a pellet shaped airsoft round would not work. Especially with a round nose. Why does the velocity need to change?

The design I have works with round BB's or not hop up at all and pellet shaped rounds, which unfortunately I need to make to test. how those work with no rifling is the question.

As far as the tower, not sure that is any better than how they make them currently or how they make metal bb's for that matter. If it works, whihc I doubt it would be cheaper than all the automated machinery.

I say you try it!

 

[awagg]

Yeah, every one says "no way, no way" to pellets, but yeah, try it! Considering low grade pellet guns shoot accurately at 600 fps with only some drop, you're almost field ready. So get your ass on the drawing board, and give us some details!

Pellets will also more much, much more accurate the a sphere, even without rifling. The aerodynamics would also help them carry more than a BB, and the gyro-stability of the rifled round would kick ass in balance and range. Hardest part is definitely the hop-factor. I would first see how they will work with a normal weight. But, a lighter pellet could carry further, but possible be unstable unless you had rifling, which would make is stable again. Idea...?

 

[lainthecity]

AARRRGGG!!!

So many cross thread discussion! I'm having a hard time keeping track of it all.

You need to remember that bb gun pellets are metal, and as a result are more dense than airsoft bbs, or theoretical plastic airsoft pellets. This means that at 600fps, scaled to a ligher round = much higher fps. Then, you need to increase size from .177 to ~.236, again still plastic, and lower the fps to safe levels.
Biggest worry of mine right now is that pellets might need a large MED to be safe, accidental discharge or malicious intent at close range could be VERY dangerous.
But if airsoft pellets will work, the OOTB accuracy would be several fold increased. Plus, you get rid of pesky hop up chambers!

 

[becklr1]

Started a separate BB vs pellet thread. Pretty sure this thread is about making plastic bb's by dropping them in water from up high.

Check for BB vs Pellet thread to keep it clean and easier to find.

 

[awagg]

You need to remember that bb gun pellets are metal, and as a result are more dense than airsoft bbs, or theoretical plastic airsoft pellets. This means that at 600fps, scaled to a ligher round = much higher fps. Then, you need to increase size from .177 to ~.236, again still plastic, and lower the fps to safe levels.

Not valid. Heavier bb's are more effected by gravity, and drop faster. Therefore the airsoft bb would drop slower, allowing for a lighter spring, bringing us to where we are right now.

Someone needs to test!

But yeah, lets more this discussion into the other thread.

 

[bobgengeskahn]

I actually have moved more to the idea that I would be casting my own custom shaped BBs if I decide to go down that route, I just thought this would be interesting knowledge to share if anyone would be so inclined or had the capacity to test such an idea for our aplication.

 

[awagg]

I THINK shot balls are pretty imprecise, because that's kinda the point, a big cloud of metal. But anyways, I think you're on to something. Maybe something, like a mechanical syringe, that only shoots out a precise amount of plastic. These would then fall into a tub of water. They would just have to cool enough to get there and not deform.