blow-forward pellet gun

[VH_man]

lol. the syringe says "single use only......." guess youll only get single shot..... lol.

kidding. the auto bit should work if you have some method of flow control, and a strong spring..........

[Acdcmonkey1991]

I truly can't wait to see this finished.

[mark.f]

Lookin good. I've always thought of a blow-forward bolt in a different way, though. I always thought a blow-forward bolt to equal: bolt with slightly restricted porting at the back, so when the valve opens it is pushed forward, misaligning the hole in the top of the bolt with the flow of ammo from the magazine.

I GUESS your idea works too. Just kidding! It's a good idea, and I can't wait to see some sort of finished prototype version, if not some uber-cool completed pellet rifle version.

[jackssmirkingrevenge]

I can't wait to see some sort of finished prototype version, if not some uber-cool completed pellet rifle version.

Just a matter of time, here is the epoxy curing annoyingly slowly.

I was thinking that if it works, the final result would be modelled on the M60, with a significant on-board air supply for limited "standalone" shots but retaining the facility to be hooked up to a compressor for longer bursts.

[spanerman]

what are you planing on using for a mag? and btw looks very promising so far..

[jackssmirkingrevenge]

what are you planing on using for a mag? and btw looks very promising so far..

It depends how much time the bolt allows the loading port to be open - if it's too short, it might have to be spring loaded. Ah well, it has to work first *bites fingernails*

[jackssmirkingrevenge]

Well, here's the finished article, ready to be hooked up to my compressor - to be tested within the next six hours, stay tuned for whoops of joy or cries of despair.

Some modifications I can forsee include making vent holes in the area in front of the bolt piston to prevent the air being compressed while the bolt is moving forward, as well as connecting the area behind the bolt to a bigger chamber to make more air available for each shot.

[noname]

I've just got one question. This iss your "holy grail," and it only took a day or two, so why didn't you make it earlier? You were registered on SpudTech for quite a while.

[jackssmirkingrevenge]

I was always looking for a simpler way to achieve things - personally I prefer to spend a long time scribbling before actually getting started making something. With this I finally decided that it can't really get any simpler so might as well give it a go.

[Redcoat]

Jack, WHat vale are you using? a blowgun? What PSI?

I'm thnking about making a single shot pellet gun based around this.

[jackssmirkingrevenge]

These tests are done at 110 psi using the very limited flow from one twist of the small screw valve at the compressor tank - so the power potential for this is much greater, I want to try and hook it up to a decent 1/2" ball valve and see what happens.

Have a look here (scroll down to the vids) - with a long enough barrel and using quick pressure on the blowgun, you can get very decent power using this setup.

[jackssmirkingrevenge]

Following the success of the increased flow and omg we has semi-auto yay!, I've been pondering if this is worth the complication (cheers to this project for inspiration)

[VH_man]

ahhh yes. the power of the quick release valve..............

i dont see why that wouldnt work...... honestly. it would be extremely fun to see the thing you had firing.... RATATATAT.........

and i just realized your problem with the slow-returning bolt can be solved....

what I think is happening is the bolt has to overcome pressure when its returning, so therefore..... well........ theres ya problem. id bet money that if you pulled the bolt into the foward position and then took the blowgun off and then let go of the bolt, the bolt would go SNAP back into place.........

[jackssmirkingrevenge]

what I think is happening is the bolt has to overcome pressure when its returning, so therefore..... well........ theres ya problem. id bet money that if you pulled the bolt into the foward position and then took the blowgun off and then let go of the bolt, the bolt would go SNAP back into place.........

A longer spring as suggested in the other thread would be an easier fix, I must admit I was a bit conservative with the one I added but yeah, the power is there - even at 50 psi, the air exerts a force of over 50 lbs on the bolt so it would have no problem moving it.

[VH_man]

it might even increase power with a lower-flow trigger mechanism...........

if youre using a small chamber, i wouldnt risk it, seeing as the pressure might not be enough to make the bolt slide foward all the way and still have enough pressure to shoot the bb.........