Thanks Dave!
The link worked a treat and I'm printing off the pages now.
(For anyone interested its at;
http://users.skynet.be/mario.severi/...0%20strip.html and he has lots of other strip down procedures for other guns + scopes there too!).
We did a couple of test fires earlier and it was chrono'ing at just under 500fps (in .22), but its noticeably 'fluffy' in all the crevices and the inside of the breech looks revolting. Not quite sure whats stuck to bits of it, it almost looked like the remnants of some sort of seal, but they seem to be liberally dotted all over the place. Little white waxy blobs.
I will post regular updates as to what we find lurking inside....