Philrob,
Its easy to change the caliber on these, I moved from .22 to .177 with mine.
You just need the barrel / compression cylinder assy. iirc Jonh Knibbs has them in stock, and iirc the cost was about £45. You can give it a full service when yo strip and rebuild it. As far as i can tell the springs etc are the same across calibers, Ive had no probs with mine since I changed over.
The only downside I can see is it says .22 on the overlever on mine, but a .22 pellet wont fit in the hole
hth
Dave
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