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Posted: Sat Apr 16, 2011 9:04 am
by POLAND_SPUD
Yeah, I admit that is impressive
However, this round is for a railgun for god sake... not a spudgun
so directly translating that into the design of your round isn't the best idea
I think I know a simple yet clever way to achieve what you want...
get a long pvc pipe (~1metre, possibly longer), make a nice streamlined nose cone for it, once it's done fill it with something heavy... attach the nose cone to the pipe and your done
If you allow the nose cone to separate upon impact you might not need a recovery system
Posted: Sat Apr 16, 2011 9:35 am
by LeMaudit
Poland, your goal is not distance, it is destructive power
Anything that long without stabilizing fins will tumble. In term of power, that's true, if you get the tube in the face from the side, it's even better! lethal within 1 meter radius

Posted: Sat Apr 16, 2011 12:22 pm
by POLAND_SPUD
check this gun...
Flaring the end might be a pain... so replace the flare with a 1 cm long section of pipe
http://www.spudfiles.com/forums/gps-tar ... rt,30.html
http://www.spudfiles.com/forums/files/p ... es_987.jpg
Posted: Sat Apr 16, 2011 3:00 pm
by LeMaudit
Flaring the end might be a pain...
Nah, you got me wrong here... flaring the end might be the fun!

Quite interesting, thanks for sharing.
I never have thought that flaring was enough to stabilise.
so replace the flare with a 1 cm long section of pipe

As it is said, flaring must be perfect. I'm not sure this would do.
I have to find that research in spudtech.com...
Posted: Sat Apr 16, 2011 3:11 pm
by POLAND_SPUD
it's here ->
http://www.spudfiles.com/forums/pvc-rockets-t302.html
I guess that flaring is just one way to increase base drag and shift cp to the tail (which keeps the projectile stable)
so at least in theory anything that increases base drag will work

Posted: Sat Apr 16, 2011 3:13 pm
by LeMaudit
Ah, thank you very much!!
[edit] now I'm thinking that a tool designed to "sandwich" the tube under heat, and press inside like a die could make those flares reliably and consistently

I'll think about that after my sabot. Looks like fun.
[more edit] and it could also shape the nose that way... hmmm... an ammo press/shaper from a length of plastic tubing

! Yup... fun...
Posted: Sat Apr 16, 2011 3:29 pm
by POLAND_SPUD
I am lazy so for me a reducer seems like the best option
This could be the VolksFlugkörper of spudding community
Cheap easy to produce and relatively well performing
(the dude from my link achieved 500 yards with these rounds... and his gun was relatively weak when compared with MrC's hybrid)
Posted: Sat Apr 16, 2011 5:24 pm
by MrCrowley
I guess I could make one just for fun, doesn't look like it would be particularly difficult once the flaring is sorted out.
Posted: Sun Apr 17, 2011 12:46 am
by Insomniac
I'm not sure you'd even need flaring. I get the feeling that a tube of the right length, with weight distributed correctly, could be quite stable. Much like a javelin, or a nerf dart. (I realise javelins don't self correct very much, but they DO try to go nose-first.)
Posted: Sun Apr 17, 2011 12:53 am
by jackssmirkingrevenge
Insomniac wrote:I'm not sure you'd even need flaring. I get the feeling that a tube of the right length, with weight distributed correctly, could be quite stable. Much like a javelin, or a nerf dart. (I realise javelins don't self correct very much, but they DO try to go nose-first.)
That was the point of this
experiment suggestion.
Posted: Mon Apr 18, 2011 1:30 am
by Insomniac
Another note... I've found a fairly low-cost ammo which, while not offering the sectional density of a metal projectile, ought to fly a hell of a lot better than most things people shoot...
I've got a couple, and they're made completely of a very dense, fairly rigid rubber material. With a decent sabot, I can see these things flying pretty well. They are stable in the air, though due to their weight they take a while to self-correct. They might be useful as a way of testing recovery methods for more advanced rounds.
Posted: Mon Apr 18, 2011 2:03 am
by jackssmirkingrevenge
Looks a bit like an
Aggregat-4 if it were made into a fun female stimulator

... would make an interesting mould, or it could be drilled out and filled with something heavier, or the tail section could be mated to a heavy nose... nice find!
It's interesting that the
premise of the toypedo is similar to the purpose of this thread, achieving long range for a given force.
Toypedo is dangerous if aimed at other people, however there are no documented fatalities
Good to hear
Also, would you market a toy for children with a name that ends in "pedo"

Posted: Mon Apr 18, 2011 2:58 am
by Insomniac
If you think those little ones (Toypedo Bandits) look a bit suss...
Wait 'till you see
the original.
And more useful to us, is what appears to be a
larger version, and one that
has LEDs and lights up.
Posted: Tue Apr 19, 2011 10:05 am
by jackssmirkingrevenge
Interesting and disturbing in almost equal measures
About flared tail stabilisation, take a look at the M865 120mm tank training round:
The tail cone segment of the subprojectile, due to the nine hole (old design) or six slot arrangement, causes aerodynamic slowing of the subprojectile to limit its range to 8,000 m.
Only 8,000 metre, pfft.
Posted: Tue Apr 19, 2011 10:10 am
by LeMaudit

this holes would limit the range? How's that? On the contrary I would have thing they help to stabilize the flight.
BTW, Beautiful holes I say...
