Logo
HomeForumCannonsWikiAlbumArchive
SpudFiles
Users  Rules   Search  Search   Chat  Chat   FAQ  FAQ   Memberlist  Memberlist   How-To  How-To   Other  Other
Register  ::  Log in Private Messages


Random Cannon

Recent topics
» SDR-21 for a noob
by frankrede on 09/06/2008 22:53 PM

» A warning to all Australi
by kaa-boom on 09/06/2008 22:46 PM

» my 1st pneumatic
by The Engineer on 09/06/2008 22:36 PM

» Homemade Regulator?
by explsvcookie257 on 09/06/2008 21:21 PM

» H2O2
by D_Hall on 09/06/2008 21:12 PM

» Airsoft Ammo Size
by Kash munni on 09/06/2008 20:47 PM

» New to the forums - my 2n
by Boom_erang on 09/06/2008 20:44 PM


Donate

Hi Guest!
As you're not registered, some features could be unavailable. Click here if you want to become a member of SpudFiles
Username:    Password:      Log me on automatically each visit    

Post new topic  Reply to topic
Goto page Previous  1, 2
 Shotgun Powered by... « View previous topic :: View next topic » 
Author Message
judgment_arms
PostPosted: 01/09/2007 19:32 PM    Post subject: Reply with quote

The Judge
Brigadier General

Joined: 17 Oct 2006
Posts: 1216
1363.81 Spud Bux

Yes, but it’ll involve a little bit of research, I need to now the rate of twist required to stabilize a paintball at 300fps… I tried the green hill formula but, then after spending about an hour figuring it out I found out that it only works on lead or lead core bullets… you seem to know quite a lot about math perhaps you’ll be able to figure this out…
Back to top
shadowghost21
PostPosted: 01/09/2007 19:38 PM    Post subject: Reply with quote

Specialist
Specialist

Joined: 19 Sep 2006
Posts: 47
125.46 Spud Bux

Well any sort of spin will help stabalize it in air. TO do everything from scratch (With out a forumla) I would have to derive a new formula and that might take some time. How are you putting spin on your paintball? If you tell me the FPS and (and how many revolutions it will do in the barrel the barrel length I might be able to tell you the velocity that it will spin in air.

-shadow
Back to top
judgment_arms
PostPosted: 01/09/2007 19:41 PM    Post subject: Reply with quote

The Judge
Brigadier General

Joined: 17 Oct 2006
Posts: 1216
1363.81 Spud Bux

Well, I plan on making a rifling machine…just a sec let me find the link to my paintball rifle, that should explain a bit.

Edit:
Here’s the link: paintball RIFLE
Back to top
shadowghost21
PostPosted: 01/09/2007 19:52 PM    Post subject: Reply with quote

Specialist
Specialist

Joined: 19 Sep 2006
Posts: 47
125.46 Spud Bux

I was reading another forum about long barrel and accuarcy and green hill forumula take a look at it.

http://www.nnypaintball.com/viewtopic.php?t=246&sid=d1b5418f03ce48dac9 fda421d1a88af6

EDIT: I wouldn't bother rifling the barrel, unless its a really low spin like 3 or 4 revolutions per inch. Just use a longer smooth bore barrel that is really close the the Diamater of a paintball.
-shadow
Back to top
judgment_arms
PostPosted: 01/09/2007 20:16 PM    Post subject: Reply with quote

The Judge
Brigadier General

Joined: 17 Oct 2006
Posts: 1216
1363.81 Spud Bux

one guy in link wrote:
I wouldn't think rifled barrels would be as accurate. From everything I've seen and read putting spin, even a uniform spin, on a paintball is bad because it wobbles in flight. Shooting a paintball is like shooting a waterbaloon full of Jello. It deforms in flight, if it spins due to its elastic property of its shell and its sweet liquid filling would be off-center due to friction on the sides of the paintball.
The only theory I could think of, where this might work, is picturing the paintball and its components like a gyroscope. As the balls sit in the hopper waiting to be shot the goo is dictated by gravity and settles to the bottom, when fired it all moves to the back of the ball, if you could spin the shell alone with the paint-like-nectar in a static state as the shell revolves around it you could have a good flight.
In a perfect world this would hold true, but then again we on earth have to deal with friction which would drag the paint on the inner lining of the shell making it lopsided in its spin.
Plus the whole while the paintball would be more of an oblong elipse because of acceleration due to firing. The paintball is accelerated from a static state (0fps) to 300fps in about a millisecond! With a shell that is meant to break on impact I'm thinking the paint would be in the back of the shell (due to a heavier density) while the whole shell enlongates until it reaches its terminal velocity. Then the shell would contract to conform back to its natural shape (circular) and then impact. If all environmental factors are ignored, ie wind currents, relative humidity, precipitation, all components of the paintball would be moving at 300fps and would be in accord. At this speed the greatest potential for precise flight is possible. Until that rotten gravity gets a hold of it and A)Sends it to earth B)Hits something other than the target C) Hits Scott or if your lucky D) Hits the target. This kind of stuff never ceaces to amaze me.


This guy made a good argument, but the thing is my barrel is 36inches, by the time it leaves the barrel every thing should be stabilized, the only thing would be if the improvement would be visible in the 18inch test barrel. But with the full sized rifle I think by the time it leaves the barrel, due in part to a slower acceleration, the paint should be pretty well balanced out, seeing how it’s bean spinning for 36inches…but then again you’re the math genius not me, what do you think?

I type to slow,
But anyway, rifling rate of twist is going to be somewhere between 1 in 41, and 1 102 inches. So not even a complete revolution.
Back to top
shadowghost21
PostPosted: 01/09/2007 20:20 PM    Post subject: Reply with quote

Specialist
Specialist

Joined: 19 Sep 2006
Posts: 47
125.46 Spud Bux

I think it will be okay, the only real way to find out is to test. Thats how I do everything. Build First, thoery later, after you shot somthing hehehe.


-shadow
Back to top
judgment_arms
PostPosted: 01/09/2007 20:30 PM    Post subject: Reply with quote

The Judge
Brigadier General

Joined: 17 Oct 2006
Posts: 1216
1363.81 Spud Bux

Figures,
Thanks, I’ve got a lot of work to do, rifling machine’s going to be complicated to make, do in part to lack of specialized tools.
Back to top
Display posts from previous:   
Post new topic  Reply to topic Goto page Previous  1, 2

Jump to:  



You cannot post new topics in this forum
You cannot reply to topics in this forum
You cannot edit your posts in this forum
You cannot delete your posts in this forum
You cannot vote in polls in this forum
You cannot attach files in this forum
You can download files in this forum


SpudFiles Version 7.0
Template based off DAJ Glass Template by Dustin Baccetti
Photo Album Addon © 2002-2003 by Smartor
Powered by modified phpBB © 2001, 2005 phpBB Group