Spot on Coburn
I've only extended the stroke by 4mm and I've opened the second ring groove out to take a 3.5mm cross section O ring and I've altered the transfer port a little bit.
I'm working on an old abused action I bought off here just to get a .177" barrel, when I got the action it was fitted with an OX mainspring and the trigger housing welds had split through the pressure.
Unfortunately I hit 800fps last night and then the power started to drop off today with each shot taken.
It looks like I've blown the seal where the breach screws into the tube.
Besides "Cheap and Tasty", Nigel Curtis had a bash at an Osprey in SAR using a Hawk MK1 PTFE piston head.
The most obvious head to use now is a Weihrauch 25mm one as the bore and stroke of a Hawk/Osprey is about the same as a MK1 HW77.
All the best Mick
Hawks, don't you just love them. I like the safety catch on the MK3 that doubles as the trigger on some examples!
Not that the members of the Merton Air Rifle & Pistol club in 1983 at an early FT shoot at Hippescombe Farm didn't like the Hawk and its derivatives
http://i451.photobucket.com/albums/q...istol-club.jpg
A Hawk MK2, two Ospreys and a Vulcan. My proper gun, a HW80 was hiding in the VW!
Last edited by coburn; 28-12-2011 at 07:34 PM.