As promissed --- Hawk MK1 and MK2 actions side by side
http://i1138.photobucket.com/albums/...0_12010003.jpg
http://i1138.photobucket.com/albums/...0_12010001.jpg
http://i1138.photobucket.com/albums/...0_12010002.jpg
Unfortunately Guy when I got my Hawk MK2 out I noticed that some fool had sleeved the transfer port down --- I can't even remember doing it.
So I can't try your experiment.
Here's a picture of my spare cylinder showing what the sleeve looks like when fitted.
http://i1138.photobucket.com/albums/...0_12010005.jpg
Now I'm pretty sure that I haven't put a new spring inside the complete .22" Hawk MK2 shown since about 1977 so I ran it over the crono to see what power it was putting out with the sleeved breach --- 9.46ftlbs with 14.5 grain pellets.
As I couldn't remember fitting the transfer port sleeve perhaps I have been inside it, I'll just have to open it up over the weekend to check, but I'm 100% sure I've not bought a spring for it since 1977.
All the best Mick