PDA

View Full Version : why some german canons advance making spirals

raaaid
05-18-2004, 06:46 AM
I understand the cannon is grooved in the inside so the bullet spins but there are several things that i dont understand:

were the germans the only ones to have this grooved cannons or everybody had it but there was something el special on german cannons that made tracers go in a spiral?

if the bullet is thrown out of the cannon spinning shouldnt it spin around its center of gravity, if it goes making spiral trajectory it means the spinning axe would be far from the bullet center of gravity(there would be more mass of bullet on one side of the spinning axe than on the other creating a centrifugal force) in fact would be so far the spinning axe it would be outside the bullet

isnt against law of mechanics have another movement besides rotation and translation that would be this spiral movement?

wouldn this mean that if you make an object have a very fast circular trayectory it will keep it instead of going in a straigth trajectory by the tangent of the circle trajectory as it should, instead it keeps this circular trajectory contradicting the basics of physics

thanks in advance to anybody who throws some light into this because it has me totally confused

raaaid
05-18-2004, 06:46 AM
I understand the cannon is grooved in the inside so the bullet spins but there are several things that i dont understand:

were the germans the only ones to have this grooved cannons or everybody had it but there was something el special on german cannons that made tracers go in a spiral?

if the bullet is thrown out of the cannon spinning shouldnt it spin around its center of gravity, if it goes making spiral trajectory it means the spinning axe would be far from the bullet center of gravity(there would be more mass of bullet on one side of the spinning axe than on the other creating a centrifugal force) in fact would be so far the spinning axe it would be outside the bullet

isnt against law of mechanics have another movement besides rotation and translation that would be this spiral movement?

wouldn this mean that if you make an object have a very fast circular trayectory it will keep it instead of going in a straigth trajectory by the tangent of the circle trajectory as it should, instead it keeps this circular trajectory contradicting the basics of physics

thanks in advance to anybody who throws some light into this because it has me totally confused

BaldieJr
05-18-2004, 06:55 AM
Just make sure they hit the target. Nothing else really matters.

http://ubbxforums.ubi.com/images/smiley/16x16_smiley-very-happy.gif

<pre class="ip-ubbcode-code-pre">
My Specs (read 'em and weep):
* Automatically grinds whole beans before brewing
* Fully programmable 24 hours in advance
* Brew Pause feature lets you enjoy a cup before brewing has finished
* Automatically shuts off when brewing is complete
* Grind-off feature for brewing ground coffee
* 1-4 cup feature to accommodate coffee for one
* 10-cup double-wall insulated thermal carafe to keep your coffee hot long after brewing
* Gold tone commercial-style permanent filter eliminates the need to buy coffee filters
* Charcoal water filter removes impurities from the water
* Separate grinder chamber and filter area allow for easy cleanup
* Limited 3-year warranty
</pre>

Curly_109
05-18-2004, 07:11 AM
I do not understand it either... but it's pretty funny... only german cannons. However I've little knowledge about matemathics & physics http://ubbxforums.ubi.com/images/smiley/crazy.gif

Would like to see answer also http://ubbxforums.ubi.com/infopop/emoticons/icon_biggrin.gif

Col.Flanders
05-18-2004, 07:20 AM
Maybe the depth of the rifling (whatever the term) combined with the calibre of round causing that pattern through the air?? The round is obviously spinning on its own axis. Dunno...

moksha
05-18-2004, 07:28 AM
I think it's to do with a piece of code borrowed from quake 2.

Cajun76
05-18-2004, 07:29 AM
I'm pretty sure it's not doing a Metroid or Contra type circular motion........ http://ubbxforums.ubi.com/images/smiley/16x16_smiley-very-happy.gif

The round is obviously not doing barrel rolls, so my best educated guess would be that the powder and/or tracer smoke is leaving the body of the round from one side, and is being thrown out and whipped behind as the round spins forward.

Good hunting,
Cajun76

http://img12.photobucket.com/albums/v30/Cajun76/Real_35a.gif
What if there were no hypothetical questions?

Jippo01
05-18-2004, 07:53 AM
As Cajun said. Shells fly straight as usual, spiral some comes from tracer burning not symmetrically and rotation of the projectile (all of which is quite normal http://ubbxforums.ubi.com/infopop/emoticons/icon_smile.gif ).

-jippo

LeLv28 - Fighting for independency since 2002
http://www.lelv28.com

Falkster's Ju-88 fan site:
www.ju88.de.tf (http://www.ju88.de.tf)

plumps_
05-18-2004, 08:35 AM
What you see is the smoke ejected smoke tracers. It's not the trajectory of the bullet itself, but the smoke spread around it.

-----------------------------------
http://home.arcor.de/rayluck/sturmovik/stulogo-banner.jpg (http://home.arcor.de/rayluck/sturmovik/)

lil_labbit
05-18-2004, 08:49 AM
The projectile does not fly in a spiral. It flies in a ballistic line and is stabalized by the spinning (gyro effect). AFAIK all guns/cannons had spirals in them to stabalize projectiles (get them spinning) - not counting real old ones http://ubbxforums.ubi.com/infopop/emoticons/icon_wink.gif

http://members.home.nl/lil.labbit/lilseesya.jpg
Night is better than Day

raaaid
05-18-2004, 08:50 AM
that would be the answer but why only the germans?

maybe they were using excentric bullets banned by geneva agreement

Supr
05-18-2004, 08:53 AM
one word

Vortex

Cajun76
05-18-2004, 08:57 AM
<BLOCKQUOTE class="ip-ubbcode-quote"><font size="-1">quote:</font><HR>Originally posted by raaaid:
that would be the answer but why only the germans?
<HR></BLOCKQUOTE>

Because the Germans were using German ammo..... http://ubbxforums.ubi.com/images/smiley/10.gif http://ubbxforums.ubi.com/images/smiley/blink.gif http://ubbxforums.ubi.com/images/smiley/88.gif http://ubbxforums.ubi.com/images/smiley/blink.gif http://ubbxforums.ubi.com/images/smiley/35.gif

Good hunting,
Cajun76

http://img12.photobucket.com/albums/v30/Cajun76/Real_35a.gif
What if there were no hypothetical questions?

Red_Storm
05-18-2004, 09:35 AM
It's historically accurate. I at first thought it was a bit unrealistic too, until I took a look at a Bf-109 guncam. It looks exactly like the tracer smoke we have in FB. It was a Bf-109G-2 shooting a LaGG-3 if I'm not mistaken.

---

Stalker58
05-18-2004, 09:53 AM
Yeahm realistic, OK and now I want see La7 Shvak guncam footage...http://ubbxforums.ubi.com/infopop/emoticons/icon_biggrin.gif

Altitude, speed, manoeuvre and.... CRASH!

Hawgdog
05-18-2004, 09:57 AM
<BLOCKQUOTE class="ip-ubbcode-quote"><font size="-1">quote:</font><HR>Originally posted by raaaid:
but there are several things that i dont understand:<HR></BLOCKQUOTE>

http://ubbxforums.ubi.com/images/smiley/88.gif http://ubbxforums.ubi.com/images/smiley/88.gif http://ubbxforums.ubi.com/images/smiley/88.gif

http://img5.photobucket.com/albums/v22/HawgDog/sharkdog.gif
When you get to Hell, tell 'em HawgDog sent you!

http://img5.photobucket.com/albums/v22/HawgDog/says.jpg

Baltar
05-18-2004, 10:08 AM
The answer is obvious: German cannons are rail guns http://ubbxforums.ubi.com/infopop/emoticons/icon_biggrin.gif

JaBo_HH-BlackSheep
05-18-2004, 10:38 AM
AFAIK it was used to help the pilot tracking his bullets, but i think and only think that it was not used on the small Guns, because u have mostly 1000 rounds for them (MG17 e.g) so no need for this, besides it's covering your target, add this to the Flashes we all have and u can't follow ur small guns hitting the target (just compare Brewster vs 109G6 small guns, try to track the 131/cal 0.50, gues what....
... jep u can't track them well.

just my 2cent

http://www.g-c-p.de/sigbib/hh/blacksheep.jpg

raaaid
05-18-2004, 10:43 AM
someone mentioned vortex and that makes me wonder why german engineers liked so much spirals (or vortex) they put spirals in the propellers and in the tracers

maybe they were influenced by shauberger who was put into prison by hitler and made him study about antigravity

shauberger claimed that air put into high spin (creating a vortex) would not only be an antigravity device but also would be self supported not needing an energy source once started and being able to be an energy source itself

maybe the allies found out this tecnology and keep it secret, who knows

lil_labbit
05-18-2004, 10:58 AM
<BLOCKQUOTE class="ip-ubbcode-quote"><font size="-1">quote:</font><HR>Originally posted by raaaid:
someone mentioned vortex and that makes me wonder why german engineers liked so much spirals (or vortex) they put spirals in the propellers and in the tracers

maybe they were influenced by shauberger who was put into prison by hitler and made him study about antigravity

shauberger claimed that air put into high spin (creating a vortex) would not only be an antigravity device but also would be self supported not needing an energy source once started and being able to be an energy source itself

maybe the allies found out this tecnology and keep it secret, who knows<HR></BLOCKQUOTE>

Yeah right http://ubbxforums.ubi.com/infopop/emoticons/icon_wink.gif "self supported" hehehe "anti-gravity" LOL - no way... you DO have a drop in gravity (about 20%) with a hovering superconductor though http://ubbxforums.ubi.com/infopop/emoticons/icon_biggrin.gif - but that's still not anti-gravity http://ubbxforums.ubi.com/infopop/emoticons/icon_wink.gif it's a quantum phenomonon.

http://members.home.nl/lil.labbit/lilseesya.jpg
Night is better than Day

Chuck_Older
05-18-2004, 11:05 AM
I've seen footage of Soviet Il2s firing at ground targets with the same spiral trails. Just last week, on History International. They did a nice segment on the battle of Kursk.

*****************************
The hillsides ring with, "Free the People",
Or can I hear the echoes from the days of '39?
~ Clash

Kurfurst__
05-18-2004, 11:18 AM
<BLOCKQUOTE class="ip-ubbcode-quote"><font size="-1">quote:</font><HR>Originally posted by Red_Storm:
It's historically accurate. I at first thought it was a bit unrealistic too, until I took a look at a Bf-109 guncam. It looks exactly like the tracer smoke we have in FB. It was a Bf-109G-2 shooting a LaGG-3 if I'm not mistaken.<HR></BLOCKQUOTE>

Yep, when I saw the tracers for the first time, I was amazed. Man, THESE move, bahave just like you saw it on guncams! Unbelievable!

As for a reason.. I guess one was probably the Germans used a typically used cannons, which had fired large round, and hence the denser, more noticable smoke from the larger round.
The other is maybe they used different smoke material than others, with longer burn time.

http://www.x-plane.org/users/isegrim/fat-furred%20tigerB.jpg

"We've got the finest tanks in the world. We just love to see the German Royal Tiger come up on the field".
- Lt. Gen. George S. Patton, Jr. Febuary 1945.

"One day a Tiger Royal got within 150 yards of my tanks and knocked me out. Five of our tanks opened up on him at ranges of 200 to 600 yards and got 5 or 6 hits on the front of the Tiger. They all just glanced off and the Tiger backed off and got away. If we had a tank like that Tiger, we would all be home today."
- Sgt. Clyde D. Brunson, US Army, Tank Commander, February 1945

peterm1
05-18-2004, 11:13 PM
Achtung

Veee hav vays off making you shpin!

Art-J
05-19-2004, 04:33 AM
I have a book about construction of ammo, explosives and bombs used in Polish Air Force in 1920s and 30s. Article about european cannon ammo describes different ways of making smoke tracers for cannon shells. The tracer shape comes from different locations of hole drilled in shells jacket, a whole where ignited phosphorus comes out, producing smoke. The book describes a shell invented after WWI, which was drilled not at the back but at the side of the jacket. As a result rotating shell produced spiral-shaped smoke trace. The article was not about specific German ammunition, but I suppose the same idea was used by Germans (and maybe others) as well.

Oak_Groove
05-19-2004, 07:00 AM
Such visual effect can be caused by the yaw angle of the projectile.

XP2500 OC'ed 11x200
768MB TWINMOS DDR 400 3-3-2.5-11
A7N8X-D Rev. 2.0/Bios 1.7
SAPPHIRE R9700 Atlantis
2 x IBM IC35040 40GB
Syncmaster 957P
Win XP Pro SP1
DirectX 9.0b
nForce UDP 2.45 w/3.75 Audio
Catalyst 3.7