Wanted: John Bowkett tuned Meteor

[jirushi]

With help of a friend who has good metal working skills and equipment, I tried to follow JB's Meteor tuning recipe, for as far as I know the ingredients.
Quad ring (plus almost 1 ft/lbs), 3 mm transfer port, 10 gram steel top hat, 2mm off the face of the piston head, scope stop screw, increased preload on the barrel latch spring.

Result: 10,8 ft/lbs in my Mk4 using 15.89 gr .22 JSB's. Smooth and accurate. A dry "thud" and no nasty vibrations.

The trigger is quite heavy. I need to test this setup in my Mk5, as I've found with previous equal power tests that the Mk5 trigger is way more adjustable than the Mk4 trigger.
On the Mk4 trigger, there's only one setting where the sears engage; a tiny movement either way, and it doesn't work anymore. On the Mk5, there's lots of room for adjustments. Not sure how this works.

Haven't got photos of the Mk4 yet, but here's the Mk5, which has an old spring, a green nylon Chambers spring guide, 10 grams worth of steel rings to act as a piston weight, and a Lightning barrel (the Meteor barrel was damaged by - I think - darts, and grouped like a shotgun). It's putting out 9,1 ft/lbs.

I need to work out how to secure the front stock screws better. After about 50 shots, they need to be re tightened.

Lastly, I've just received a parcel from Hsing-ee, containing another squared off piston head and Maccari piston buttons. Thank you Hsing-ee! More experimenting on the way.