Diana Model 27

[Phil Russell]

No problem. I forgot to mention last time that I expect that if a new piston head was needed then a new screw would have been used and a hole drilled for a new pin.
Don't forget you can tweek power a bit with preload.

Here are spring measurements from a pre-war 27 I have recently corrected: 38 coils, 2.7mm, 12.8 - 13.0 id. This gave me about 40mm of spring to compress before engaging trigger block coils. Old spring was identical in measures but bent and collapsed.
Cheers, Phil

[Ciaran07]

New spring arrived today the seller sent me

DIANA / ORIGINAL 27 19 13 3 245 Ox

Instead of the cobham one I mentioned earlier
I stripped the rifle put new spring in it was flush
With the end of cylinder so the length of the trigger mechanism to preload it about
2” at a guess
Now the fun starts I had an old drift pin knocking about so cut that to hold the two parts of the trigger block back retaining the smaller soft spring with this in place old jumper over the barrel and pushed down then drifted the proper pin through easier said than done didn’t change piston seal yet

With old spring was doing 450fps 8.44gn
New spring doing 620fps 8.44gn