Well, in celebration of the coming end of the "Registry" and the fact I had a bit of time (thank-you Sean)- I decided I should install a Vortek kit in a detuned .177 Airhawk that was received on a trade from Dave here on the forum (Umarex chinese copy of the Diana 34) and see what happens (Yes, I have all the licensing required for this).
Don't have pictures, unfortunately, I don't have alot of time and the quicker I could get through it, the better (and the more likely I would actually get it done before something else sidetracked the activity).
The rifle was surprisingly well built- but I also suspect someone else was inside it before I got to it- better lube than I would have expected (appeared to be an almost silicone grease mixed with some of the factory-style mystery goo), a lot less dirt, a polished piston, and reasonable guides.
It was testes beforehand, and with 7.5gr-ish pellets was a bit "hot" at 520fps average at 10 shots, no dieseling to speak of.
So, I ripped it apart, cleaned it up a bit (ground off some ragged edges on the piston slot with a Dremel) and started with the Vortek kit.
Well, dang it, of course the Vortek kit needed some "customization" for the Chinese copy- a file and sandpaper would be required to make it all fit the way it should (perimeter of seat base was too wide). 'I don't have time for this' I'm thinking- so I compare the factory guides and spring with the pieces from the Vortek kit and end up keeping only the front and rear Vortek guides, spring, and piston seal- the rest ends up in the junkpile along with the stock parts that were removed. Lube it all up nice, reinstall the trigger parts (yes, this is easier than dinking up the safety assembly by not taking the trigger setup apart). Trigger was also a pretty good copy of the genuine Diana T05 unit.
End result, a very low recoil .177 Airhawk averaging 840-850fps after a couple dozen shots (started at 840, now at 850- so it should go up a bit more before settling out I think)- went over 1020fps on the first couple of dieseling shots before whatever remnant lube I must have gotten too close to the seal was gone.
In any event, I am quite happy with the end result. Maybe if I had wanted to take the time to size all the Vortek pieces (wouldn't have changed the power output) it might be even smoother, but I'm thinking it couldn't be much better anyways. Maybe someday I'll actually have time to go and shoot the thing other than just over a Chrony...
