Quite possibly! I have used the stock hop nub and a Prommy Purple for now!
I spent the morning wiring up the gearbox. Used the stock 18AWG wiring for the trigger contacts and 16AWG for everything else. The basic Perun Mosfet is excellent as the two current wires are on the front and single trigger contact wire is on the back.
This was wired to the front as stock through a 60cm wiring loom. Decided to change to a rear mount as there is plenty of room for a battery above the fake bolt. Fits a 1450mah 7.4 stick with room to spare. It is a little difficult to close the buttpad due to the thick wiring, but placed in the correct way it will sit flush without pushing the motor towards the bevel.
Forgot to post a photo of the gearbox post upgrade yesterday.
I had some motor height issues and I forgot to put the Motor shim back in after I had reassembled it. So I had to disassemble again and put in a narrower shim then stock (The Motor height was perfect without the shim, it's slightly grindy now but its reasonable enough!).
I also changed the Maple Leaf out for the standard odd hop nub and an old Prometheus Purple that I grabbed out of my Cyma P90 (Which got the Maple Leaf and 0hm nub which thankfully fits perfectly).
Here it is in its glory. A fully charged 30C 7.4V Lipo results in a snappy trigger response which rarely locks up on semi when trigger spamming (Kind of par for the course with bullpups). It has a nice 23 RPS. It's a bit loud as the gearbox is right next to my recording phone.
FPS is coming out at a steady 277FPS on .3's which equates to roughly 339 FPS on .2's taking into account Joule Creep. With actual .2's it's more like 328.
Hopefully I'll get to test the range and accuracy soon. But (hopefully) The gearbox is complete and pretty much the project! I may add some foam into the body cavities in the future. The Silent piston head and cylinder combo didn't exactly do much!
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Working on the Tavor was not the nightmare I thought it would be. The initial take down is quite difficult as there are lots of bits to take off in a somewhat specific order. But the gearbox itself is pretty easy to work on due to the quick change spring system, a AR latch that stays put and relatively simple wiring. The AOE was correct as soon as I put in the new Piston/Cylinder/Head combo needing no changes.
I can take down the Tavor right down to an open gearbox in about 10 minutes, reassembly is about the same sort of time.