Shooting around corners.

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LeMaudit
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Mon May 11, 2009 2:43 pm

Nah… I don’t want to shoot around corners really, just a way to grab your attention :-D

But I still have a related question:

Say I have a ball bearing (1/4" or 3/8") that is pushed by compressed air between 135 and 400 psi along a cooper barrel. Do you think the beginning of the barrel could be curved, and the steel ball would negotiates the curve nicely? Up to 90 degree maybe? With a gentle curve, not a sharp angle of course! The additional inches could be a good addition for a short barrel in term of velocity, but I wonder what other problems could append...

For the curious minds, I am searching some way to make a more compact gun. And it’s all your fault guys… I was drooling about God’s work (Mr Candyman) following a forum’s links when my wife saw the screen and the beautiful Hammerli gun he made. And she said: "Wooooo… I want that!"
And no matter what I said after "but honey, my plan was to make a revolver that throw darts with a very big barrel" she just didn’t care… women…

Sorry if the question was asked before, I couldn’t find anything related in the forum search… maybe a too silly idea :D
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jackssmirkingrevenge
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Mon May 11, 2009 2:57 pm

In a word, yes.

Be careful though, that when you bend the copper tube, you don't restrict the round cross-section of the barrel.
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Ragnarok
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Mon May 11, 2009 3:00 pm

I knew Jack was going to do that when I saw the topic title, but I was expecting a working link.

I may be talking out of my behind, but I'm reasonably sure that Brian the Brain's marble machine gun had a 90 degree bend between the "breech" end of the barrel and the muzzle that the marbles had to travel around.

I don't think it had too many problems.
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paaiyan
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Mon May 11, 2009 3:01 pm

Well the first problem I see is the wear on the structural integrity of the barrel. Obviously the bearing will pick up velocity quickly and will strike the sidewall of the barrel pretty hard at the curve. That could cause some issues.

The second problem is going to be that your bearing will lost velocity as it makes the curve. An object in motion stays in motion unless a force acts upon it. The bearing will want to continue straight, but will be forced to curve by the barrel and will most likely lose significant amounts of velocity due to friction.

You'll also have to worry about accuracy. If the barrel curves left, the momentum of the bearing negotiating the curve will force the gun a bit to your right.
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jackssmirkingrevenge
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Mon May 11, 2009 3:10 pm

Ragnarok wrote:I knew Jack was going to do that when I saw the topic title, but I was expecting a working link.
Works for me. In any case, have another one ;)

Image
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ramses
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Mon May 11, 2009 3:11 pm

paaiyan wrote: You'll also have to worry about accuracy. If the barrel curves left, the momentum of the bearing negotiating the curve will force the gun a bit to your right.
also, the bearing will be spinning, so you will get the magnus effect, therefore you will be able to shoot around corners. If you have the barrel come from the top of the gun, then go forward, and you will have an uncontrollable hopup.
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Ragnarok
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Mon May 11, 2009 3:14 pm

jackssmirkingrevenge wrote:Works for me.
I'm getting 403 Forbidden errors.

It's possible that it's objecting to hotlinking, and you're only seeing it because it's in your computer's cache.
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ramses
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Mon May 11, 2009 3:17 pm

Ragnarok wrote:
jackssmirkingrevenge wrote:Works for me.
I'm getting 403 Forbidden errors.

It's possible that it's objecting to hotlinking, and you're only seeing it because it's in your computer's cache.
yep, just click on the link, copy the url, go to another site, paste it into the address bar, and there you go.

and yeah, it works for me now because it is cached in my browser.

good call
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LeMaudit
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Mon May 11, 2009 3:29 pm

The link works for me :-)

I had the idea while reading this book, while searching for cooper tubing max pressure.
http://www.copper.org/publications/pub_ ... ndbook.pdf

They say that properly done, a cooper tubing bent is even harder than a strait one. (p.42)

Yeah, I knew some pretty amazing things have being done by street fighters. Also during WW2 and even more modern wars.

The second problem is going to be that your bearing will lost velocity as it makes the curve
Good point!
You'll also have to worry about accuracy. If the barrel curves left, the momentum of the bearing negotiating the curve will force the gun a bit to your right.
The bending would be down with what I have in mind, but again good point. I didn't thought about that. Thanks for the advices!


Good to know this have being attempted successfully anyway. I'm going to explore Mr Brain's cannons :-D
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paaiyan
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Mon May 11, 2009 3:43 pm

ramses wrote:
paaiyan wrote: You'll also have to worry about accuracy. If the barrel curves left, the momentum of the bearing negotiating the curve will force the gun a bit to your right.
also, the bearing will be spinning, so you will get the magnus effect, therefore you will be able to shoot around corners. If you have the barrel come from the top of the gun, then go forward, and you will have an uncontrollable hopup.
That's true, I hadn't thought of that one. It's just like putting spin on a soccer ball when shooting.
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i-will
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Tue May 12, 2009 3:22 pm

i've though of this before. i want to try to modify a hop-up in my airsoft gun to give it an extreme side spin.
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CpTn_lAw
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Tue May 12, 2009 4:45 pm

just put your AEG on the side, it'll work ;) i know that by experience!
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i-will
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Wed May 13, 2009 3:31 am

yeah, that is much simpler. still the standard hop-up doesn't give enough spin for it to curve at a useful distance. some sort of modded hop-up will be needed.
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inonickname
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Wed May 13, 2009 3:59 am

LeMaudit wrote:The link works for me :-)

I had the idea while reading this book, while searching for cooper tubing max pressure.
http://www.copper.org/publications/pub_ ... ndbook.pdf

They say that properly done, a cooper tubing bent is even harder than a strait one. (p.42)

Yeah, I knew some pretty amazing things have being done by street fighters. Also during WW2 and even more modern wars.

The second problem is going to be that your bearing will lost velocity as it makes the curve
Good point!
You'll also have to worry about accuracy. If the barrel curves left, the momentum of the bearing negotiating the curve will force the gun a bit to your right.
The bending would be down with what I have in mind, but again good point. I didn't thought about that. Thanks for the advices!


Good to know this have being attempted successfully anyway. I'm going to explore Mr Brain's cannons :-D

That's because copper work hardens.

On the whole I wouldn't, it's not the correct way to use forces to your advantage..A detent or homemade hopup is a better option.
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LeMaudit
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Wed May 13, 2009 8:12 am

Ah, one more thing to learn... I'm going to check what this "hopup" means... thanks for the advices.
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