Login    Register
User Information
Username:
Password:
We are a free and open
community, all are welcome.
Click here to Register
Sponsored
Who is online

In total there are 71 users online :: 4 registered, 0 hidden and 67 guests


Most users ever online was 155 on Mon Aug 15, 2016 1:40 am

Registered users: Bing [Bot], Google [Bot], MSNbot Media, Yahoo [Bot] based on users active over the past 5 minutes

The Team
Administrators
Global Moderators
global_moderators.png CS

prototype ballistic knife

Post questions and info about pneumatic (compressed gas) powered cannons here. This includes discussion about valves, pipe types, compressors, alternate gas setups, and anything else relevant.
Sponsored 
  • Author
    Message

Unread postAuthor: jor2daje » Mon May 09, 2011 11:23 pm

Hey crna just wanted to say thanks for this thread, I never knew these knives even existed and making them pneumatic is even cooler, yours inspired me to give it a go and Im pretty pleased with the results, for now it's only spring powered but I made an addition to the knife that adds an o-ring and I will be soldering a shrader into the handle.

It's all brass, copper, and steel the blade is made from an old chisel, range with the spring is about 25 ft which I think is fairly good, hopefully can be improved with some higher pressure from the pneumatic.
Image
Image
  • 0

Patience is a virtue, get it if you can, seldom in a women, never in a man.
User avatar
jor2daje
Lieutenant Colonel
Lieutenant Colonel
 
Posts: 418
Joined: Sun Oct 05, 2008 9:41 pm
Location: Southern California
Reputation: 0

Unread postAuthor: jackssmirkingrevenge » Mon May 09, 2011 11:56 pm

Nice, that looks like a pretty heft spring but I'll wager power as a pneumatic will be miles ahead, and will not sound as "twangy" :)
  • 0

User avatar
jackssmirkingrevenge
Donating Member
Donating Member
 
Posts: 24225
Joined: Thu Mar 15, 2007 11:28 pm
Country: Holy See (Vatican City State) (va)
Reputation: 66

Unread postAuthor: Crna Legija » Thu May 12, 2011 7:45 am

Hey very nice work there jor2daje :thumbright:, looks great! When your get around to making it pneumatic keep the spring in to see if it helps, i was going to do that but cant find a stiff spring the fits. :( Thats why i when down the pneumatic route.

i also have an update, more damage pics/vid. its only at 100psi again, because i cant find something good to shot at.


edit [youtube]http://www.youtube.com/watch?v=g2H9hf00Kgw[/youtube]
  • 0

Attachments
dmg.jpg
the target is 5 and a bit centimeters of polystyrene
dmg.jpg (32.11 KiB) Viewed 1000 times
dmg2.jpg
went right through, like its polystyrene or something.
dmg3.jpg
dmg3.jpg (17.64 KiB) Viewed 1000 times
'' To alcohol... The cause of, and solution to, all of life's problems.”
--Homer Simpson

Add me on ps3: wannafuk, 8/11/11 cant wait
User avatar
Crna Legija
Major General
Major General
 
Posts: 2333
Joined: Sun Jul 20, 2008 5:14 am
Location: australia
Reputation: 0

Unread postAuthor: shardbearer » Thu May 12, 2011 6:30 pm

crna legija, that is a really nice looking knife. The main problem with the QD is the really short "barrel" length, like an inch, and that is a beautiful solution. I am trying to think up an easier way to make one, but that seems pretty simple.

And jor2daje, nice job there. I like it. Should be pretty powerful with both spring and pneumatic.
  • 0

Last edited by shardbearer on Thu May 12, 2011 10:32 pm, edited 1 time in total.

shardbearer
Sergeant
Sergeant
 
Posts: 85
Joined: Sat Apr 23, 2011 10:21 pm
Reputation: 0

Unread postAuthor: Crna Legija » Thu May 12, 2011 10:21 pm

the blade has about 10cm of travel thats like 4''.
  • 0

'' To alcohol... The cause of, and solution to, all of life's problems.”
--Homer Simpson

Add me on ps3: wannafuk, 8/11/11 cant wait
User avatar
Crna Legija
Major General
Major General
 
Posts: 2333
Joined: Sun Jul 20, 2008 5:14 am
Location: australia
Reputation: 0

Unread postAuthor: jackssmirkingrevenge » Thu May 12, 2011 11:32 pm

Looking great!

Don't youhave a wooden plank you can test it against with the pressure ramped up?

Also, does it fly straight over distance or is there a tendency to tumble? Where is the CG?
  • 0

User avatar
jackssmirkingrevenge
Donating Member
Donating Member
 
Posts: 24225
Joined: Thu Mar 15, 2007 11:28 pm
Country: Holy See (Vatican City State) (va)
Reputation: 66

Unread postAuthor: Crna Legija » Fri May 13, 2011 1:34 am

it fly's straight for abut 5m then starts to go side ways, ill try get some shots at wood board.
  • 0

'' To alcohol... The cause of, and solution to, all of life's problems.”
--Homer Simpson

Add me on ps3: wannafuk, 8/11/11 cant wait
User avatar
Crna Legija
Major General
Major General
 
Posts: 2333
Joined: Sun Jul 20, 2008 5:14 am
Location: australia
Reputation: 0

Sponsored

Sponsor
 


Unread postAuthor: shardbearer » Fri May 13, 2011 2:16 am

About an actual ballistic knife:

The spring in these knives is powerful enough to propel the blade to about 6 meters (about 18 feet) or more at 63 km/h (39 mph). They were not without drawbacks however: Because the projectile blade had no aerodynamic or gyroscopic stabilization, it was only accurate out to approximately 3 meters. Any further and the blade would often tumble and land sideways or tail-first.


The only ways to stabilize objects are through spin, fins, or having the weight in the front, none of which are viable for knives.
  • 0


shardbearer
Sergeant
Sergeant
 
Posts: 85
Joined: Sat Apr 23, 2011 10:21 pm
Reputation: 0

Unread postAuthor: jackssmirkingrevenge » Fri May 13, 2011 2:50 am

shardbearer wrote:The only ways to stabilize objects are through spin, fins, or having the weight in the front, none of which are viable for knives.


Not necessarily. The "handle" can be made out of aluminium, which would put the CG forward with a heavy steel blade. You can even have a telescopic tube than extends on firing.

It would also make sense to have a high aspect ratio dagger-like blade fitted to a relatively wide "handle" in order to keep the CP to the rear, as well as improving penetration.
  • 0

User avatar
jackssmirkingrevenge
Donating Member
Donating Member
 
Posts: 24225
Joined: Thu Mar 15, 2007 11:28 pm
Country: Holy See (Vatican City State) (va)
Reputation: 66

Unread postAuthor: shardbearer » Fri May 13, 2011 4:21 am

To improve range you could have the barrel cover the blade, but that would defeat the ability to use it as a normal knife while in the barrel. O rings on the handle would also help range.
  • 0


shardbearer
Sergeant
Sergeant
 
Posts: 85
Joined: Sat Apr 23, 2011 10:21 pm
Reputation: 0

Unread postAuthor: al-xg » Fri May 13, 2011 7:43 am

http://world.guns.ru/grenade/rus/device-dm-e.html
If you really wanted to spin stabilise... ;)
  • 0

User avatar
al-xg
Colonel
Colonel
 
Posts: 643
Joined: Fri Jan 19, 2007 12:29 pm
Reputation: 0

Unread postAuthor: jackssmirkingrevenge » Fri May 13, 2011 10:37 am



I wouldn't be surprised if they had a knife, no shovel projectile for that thing :D as the piston is separate, it really is a question of "whatever fits in the barrel".
  • 0

User avatar
jackssmirkingrevenge
Donating Member
Donating Member
 
Posts: 24225
Joined: Thu Mar 15, 2007 11:28 pm
Country: Holy See (Vatican City State) (va)
Reputation: 66

Unread postAuthor: saefroch » Fri May 13, 2011 5:36 pm

Was that link intentional, JSR? The site it led me to redirected my browser to an X-rated website and tried to load a virus onto my computer...
  • 0

User avatar
saefroch
Major General
Major General
 
Posts: 1679
Joined: Mon Jun 08, 2009 8:47 am
Location: U.S.A.- See Map
Country: United States (us)
Reputation: 0

Unread postAuthor: jackssmirkingrevenge » Sat May 14, 2011 1:03 am

saefroch wrote:Was that link intentional, JSR? The site it led me to redirected my browser to an X-rated website and tried to load a virus onto my computer...


Certainly not my intention. It's a perfectly innocent youtube link!

http://www.youtube.com/watch?v=BXsLRD6hcrA

Weaponology : Spetsnaz - part 5


Are you sure you weren't browsing something else ;)
  • 0

User avatar
jackssmirkingrevenge
Donating Member
Donating Member
 
Posts: 24225
Joined: Thu Mar 15, 2007 11:28 pm
Country: Holy See (Vatican City State) (va)
Reputation: 66

Unread postAuthor: Crna Legija » Sat May 14, 2011 2:33 am

It worked fine for me.
  • 0

'' To alcohol... The cause of, and solution to, all of life's problems.”
--Homer Simpson

Add me on ps3: wannafuk, 8/11/11 cant wait
User avatar
Crna Legija
Major General
Major General
 
Posts: 2333
Joined: Sun Jul 20, 2008 5:14 am
Location: australia
Reputation: 0

PreviousNext

Return to Pneumatic Cannon Discussion

Who is online

Registered users: Bing [Bot], Google [Bot], MSNbot Media, Yahoo [Bot]

cron
Reputation System ©'