Quote Originally Posted by ggggr View Post
Its pretty much as Evert has said. Just think of it as a Sidelever Hawk Mk3. It is a relationship like the Mercury is to the Airsporter. I'm pretty sure that the piston can be swapped over.
Though the Airsporter MK4 onwards and Mercury pistons are interchangeable, the Hawk2/3 Pistons and Osprey Pistons aren't, Guy.
The Hawk has a cocking lever slot in line with the piston sear cutout, the Osprey has the cocking lever slot at 90 degrees to the piston sear to accommodate the sidelever layout.


Quote Originally Posted by ggggr
Regarding some exported Ospreys, I was told they got the power down by drilling the piston head a bit to create more lost volume.
Yes, it's been said that Webley drilled a void into the front of the Osprey and Hawk Pistons to lower their power for the German market.




All the best Mick