That was the gun system I was building when I purchased the gun from C/D.The I/R components came from Bill as did the modified RX-18 with fan and joy stick mod.Also why we three had the conference call. So I never was able to build due to the wait for the system that never came. And yes the system we are building has recoil and I would be happy to show you how to build the recoil,but The Tamiya barrel will have to be line bored and ataperedseat for the inner pneumatic gun barrel to self align with the Tamiya barrel,this happens at recoil and requires some other parts. The system uses parts available on line by vendors most arefamiliarwith. The whole point of us building this gun is not to take anything from C/D but to bring a design to the community that any tanker could build at home,now it will work with the Heng Long barrel,I built my Barrel for my Tiger and it is 30mm longer than stock. If someone wanted to duplicate the design of my Barrel that's fine. That is the real threat,giving away something that really works,instead of trying to sell it, but until Someone has a C/D gun and does a write-up we have agreed to keep the drawings,parts list and instructions private. I want it clearly understood that nothing in this design is in any way developed from anything C/D has ever done,recoil function has been posted on several forums and several designs.It's not that new just expensive and takes some skill,few were built because the I/R SYSTEM WORKS FOR BATTLING in an organized event,the UK guy's have to manyrestrictionsand must carryinsuranceeven at the I/R meets due to the publicattendance,and the club battle ground are connected tomuseums.Their is a group of 1/6 scale guy's who battle with painball guns,called markers. I also have a 1/6 scale Tiger,and most of these guys do have recoil.Here is the site for this group, Sax
http://groups.google.com/group/rctankcombat