SpudFiles

ssp would be good, but it's this design that i want to try to work on right now. it could also be intergrated into the design of existing nerf launchers quite easily too. something i thought of today was having a spring in front of the bolt to assist in cocking the gun by counter-acting the force of the compressed air, but not be strong enough to do all of the work so that you could still push it back into its forward position ready for firing.

for example, without the spring, if i only had the strength to pull back with 10kg of force, the pressure behind the piston would have to be pushing back with less than that force for me to be able to cock it. but if i had a spring between a stopper and the flat front face part of the bolt, which when extended to the point that the piston locks in still exerts 5kg or so of force, then the pressure behind the piston could be higher, and then i would have to push the bolt forward again acting against the spring.

am i right?

cfb_rolley wrote:am i right?

That would work, spring helps you cock the piston, once the piston sear engages you rack the spring forward and lock it in place so as not to interfere with the piston on firing, then fire, unlock the spring and repeat as necessary.

It's going to have to be quite a spring though to make a significant difference

haha yeah it will have to be. i figure it will have to be as strong as possible, as long as i can compress it. i think i can get this to work, so i'm off to the drawing board some more.

it is harder to push a bolt forward than to pull it back. When you pull it back the stock rests against your shoulder and your back muscles do the work. Pushing it forward is awkward and less muscle groups can be used.

lozz08 makes a good point, I imagine this would be more practical (and badd-ass ) with a pump-action shotgun type grip than a rifle style bolt.

that could work, people have changed the bolt on a longshot to a pump action on the front before using a kind of connecting plate setup. good news is i'm well into the actual design of it now and can make the chamber pretty large by intergrating it into the the stock, this way the piston only needs to travel 1/3 of the way into the chamber meaning the pressure will only increase by 50% (if i'm grasping the maths behind pressure increase). i can also expand it even more i think.

and, it could also be used as a bolt action combustion if a made a longer bolt that covered the hole for the trigger mech because there would be tons of room for ignition, chamber fan and gas inlet