I have started hacking my gearbox now and this is the current state:
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I removed the piston head and replaced it with a solid weight where I can screw in a long 8mm threaded rod that extends towards the front all the way through the outer barrel.
I will use the existing hole in the barrel (where the bullet counter sensor used to be) and insert a stop there which the rod will impact and this will hopefully generate the recoil force.
This is all theoretical at the moment since I haven't fired the gun yet because I need to order a new motor. I'll spend some more time tweaking this mod so any suggestions are welcome!
I might for example add a second (spring loaded) rod that extends out the back which would add some more weight to the system. As well as being able to move the bolt plate, if I want to do that.
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RifleModCU.jpg [ 280.26 KiB | Viewed 7233 times ]