The Webley Hurricane is a great tool. Plenty accurate out to 30 feet. Did you get one with the scope or just irons? I bought an old beater with the Webley scope, no irons, and it was WELL used and dirty when I bought it. After a thorough cleaning and some practice I used it to kill red wasps around my house. At 30 feet I could hit them about half the time though some required more than three shots. I wasn't in a hurry and it was a target rich environment for the first few days. Mine is worn enough that you have to be careful when closing the barrel after cocking because the little foot that slides on the guide rails will jam due to excessive clearance. But the accuracy is still superb.
Glad you found a reasonable and effective solution to your 'flying rat' problem.