Electric Semi Auto .22 Air Rifle Modification

[Binary Blue]

I am planning to convert a bolt action CO2 .22 air rifle (XS 60C) to semi/full auto by using an electric airsoft gun gearbox lower half (gears without piston) to pull back the bolt and hammer and release them.

I noticed in airsoft guns the air nozzle pushes the BB forwards into the breech before or as soon as the piston starts moving forwards. However, my design right now will have the hammer and the bolt moving together as shown below. Is there anything wrong with this method in my case you guys know of off the top of your heads?



When I came up with the design, I thought that it would be OK because the movement of the hammer does not cause the pellet to launch until the final moment when the hammer finally hits the valve, unlike AEG's where if the piston were to do the same propelling force would be applied to the BB as it was being pushed into the breech, if not sooner, but I'm pretty sure I missed something.

[jrrdw]

External battery pack or really hollowed out stock??? Getting it all in there in good alignment for smooth operation might be tricky....

[Binary Blue]

External battery pack or really hollowed out stock??? Getting it all in there in good alignment for smooth operation might be tricky....

Battery will be in a hollowed out stock attached to a receiver that will house the air gun's receiver, the bolt and hammer, and the AEG gearbox components. The bolt and hammer are stock parts of the air gun anc are already in the air gun's receiver.

The gearbox really is from an AEG. I'm going to be using the ICS lower gearbox half seen here:
http://www.ebay.com/itm/221342140489?_t ... EBIDX%3AIT
with a motor to pull back the bolt and hammer which will move together due to a pin on the hammer interfacing with a groove on the bolt.

[Binary Blue]

Update:

I decided on using a solenoid as a "hammer" instead.

Here's the testing rig:


The long rod is 1 foot of 0.75 inch diameter polycarbonate.

The solenoid I currently have is not strong enough. It pushes the rod into the valve but it's not enough to "crack" it. I forcefully pushed the solenoid core with my hand and it was enough to make the valve "crack".

This is the solenoid I'm currently using:
http://www.ebay.com/itm/350931123093?_t ... EBIDX%3AIT

This is the solenoid I'm considering:
http://www.ebay.com/itm/321523344122

Think that will be enough?

[Binary Blue]

Success!

I replaced the capacitor with one that could handle a higher voltage (63V, 2200uF) and cranked up the voltage all the way to 60V. Using the same solenoid managed to open the valve and produce a loud "CRACK!".

If you want to see it in action, take a look at this youtube video:
[youtube][/youtube]

Parts I used:
Capacitor: http://www.digikey.com/product-detail/e ... ND/2428146
Polycarbonate Rod: McMaster Carr 85485K45
Solenoid: http://www.ebay.com/itm/350931123093?_t ... EBIDX%3AIT

Now the next steps are to attach the polycarbonate rod to the solenoid, to see if I can make the hammer shorter, and to integrate a microcontroller to control the solenoid.

[Anatine Duo]

NIce! I've wanted to try this for years.

[wyz2285]

Dunno how you plan to put all the electronics into a package small enough to fit onto the gun itself. I'd lose the rod, I think you will be fine without it.
Done this before with a different approach, used a hammer valve+chamber seal piston combo. Never got a proper fire control unit for it tho. Good luck with your project.