Crossbow/mechanical marblegun/harpoongun
Posted: Tue May 30, 2006 5:23 pm
This design has been discussed before so I decided to post it here for all to see.
I've built this a long time ago.It shot a marble halfway into a solid wood door.Half of the marble was in I mean.Glass jars where fun to shoot.THey blew apart in a cloud of glass.
The advantage is, you can easily repeat shots and the gun is silent.
Disadvantage is the accuracy.
The pulleysystem I designed doubles the distance you can pull the string therefor doubling the speed but halving the power.So I just doubled the amount of rubber bands to get it back up to my maxcimum pulling force.Well not maximum but to the point I started doubting the structure would hold.I estimate it took about 40 kilograms of force to pull back the string.
Still my pneumatic gun is more powerful.(over 300 psi)
This design would work with a strong spring( or a number of them) aswell.
Without the upper aluminium strip it would be just a harpoon gun.This would be much more dangerous because of the projectiles weight and pointed shape.Accuracy wouldn't be an issue anymore.
If anybody is interested in copying this design or modifying it, I offer my help.(pretty proud of it)
I've built this a long time ago.It shot a marble halfway into a solid wood door.Half of the marble was in I mean.Glass jars where fun to shoot.THey blew apart in a cloud of glass.
The advantage is, you can easily repeat shots and the gun is silent.
Disadvantage is the accuracy.
The pulleysystem I designed doubles the distance you can pull the string therefor doubling the speed but halving the power.So I just doubled the amount of rubber bands to get it back up to my maxcimum pulling force.Well not maximum but to the point I started doubting the structure would hold.I estimate it took about 40 kilograms of force to pull back the string.
Still my pneumatic gun is more powerful.(over 300 psi)
This design would work with a strong spring( or a number of them) aswell.
Without the upper aluminium strip it would be just a harpoon gun.This would be much more dangerous because of the projectiles weight and pointed shape.Accuracy wouldn't be an issue anymore.
If anybody is interested in copying this design or modifying it, I offer my help.(pretty proud of it)