just put together a thing i had in my mind for a week. Ammo with unfolding wings like a rocket. I guess this will make it rotate and remain straight in flight
In front of and behind the wings there is a ring, which fits exactly into the barrel and seals it. between the rings, the wings with tensed springs are held smaller than the barrel diameter by a ring of paper. When the projectile leaves the barrel the wings pop out- the springs make them and the paper is just thrown away.
There is a brass cap on the tip to make it heavier an i added orange tape for better visibility.
It took nearly an hour to build(bad tools) but it's very simple. just look at the photos an you will know how it works.
Just made one test shot. Wasn't impressive (its raining and my good bike pump is broken). fired at ~~100psi hit a piece of wood. Looks like it remained straight. It's just a prototype. The unfolding works good. its just "click" and there tey are. I took the springs from my old printer.
I'll post when more testing is done. Maybe i can post a video.
Looks a bit crude but it seems like it will work well enough, almost a shame to fire it.
Note that finned projectiles don't need to be spun to be stable in flight, in fact spinning them will cause extra drag and reduce performance.
Posted: Tue Aug 21, 2007 10:31 am
by paaiyan
That's a really good prototype, quite ingenius on your part. I can say that I've seen things like this before, but I don't recall ever seeing one made for a spudgun. In order for those wings to cause spin, however, they will need to be tilted a bit, like fan blades.
Posted: Tue Aug 21, 2007 10:41 am
by Rock
I wonder where the inspiration came from Wink
Almost right. I saw a picture with some different mortar grenades and one of them had these.
I admit that i had inspiration before making it.
Here are very quick responders. (9minutes)
Posted: Tue Aug 21, 2007 9:15 pm
by Novacastrian
Uber cool! would adding more fins help, maybe one more?
Thanks for the link too Jack that's one round i would not want to be near when fired!!
Posted: Tue Aug 21, 2007 9:19 pm
by jackssmirkingrevenge
Novacastrian wrote:Thanks for the link too Jack that's one round i would not want to be near when fired!!
Wow, that is good work. Looks like this so called 'ammo contest' might not be so bad after all.
Posted: Wed Aug 22, 2007 12:42 am
by Insomniac
jackssmirkingrevenge wrote:Note that finned projectiles don't need to be spun to be stable in flight, in fact spinning them will cause extra drag and reduce performance.
In theory, yes, but a finned projectile will only go straight if it is built very precisely. Otherwise it will always have a tendancy to turn one way or another, so a slow rotation would actually improve accuracy.
And that ammo looks very cool, could you get a vid of it being fired?
Posted: Wed Aug 22, 2007 1:01 am
by Novacastrian
shud_b_rite wrote:Wow, that is good work. Looks like this so called 'ammo contest' might not be so bad after all.
What Ammo contest? Who's idea was it? When is it being held?
I WANT IN!!
P.s. Jack you never fail to surprise me with your extra ordinary ability to offer us the cream links...
FRAG-12 i like it.
It's the kinda thing that if "the Troubles" was still a full conflict would be used etc. I like it. I wonder if it will ever be put into full production.
Posted: Wed Aug 22, 2007 2:38 am
by jackssmirkingrevenge
Redcoat wrote:FRAG-12 i like it.
It's the kinda thing that if "the Troubles" was still a full conflict would be used etc. I like it. I wonder if it will ever be put into full production.
There seems to be a fashion for 20-30mm man-portable semi-auto grenade launchers like the US XM109, XM25 and South African PAW-20, this round (circa 19mm so almost equivalent payload to a 20mm shell) gives any shotgun the same destructive capability, though the specialised launchers above are intended to have complex electronic sights that feed information to the grenade fuse giving an air-burst or delay capability.
Posted: Wed Aug 22, 2007 2:49 am
by Redcoat
PAW-20 is awesome!I think i'm in love. Maybe a SPudGun replica? maybe but in the future maybe in about 6 months or so.