Being a mere whippersnapper (!), I've only ever hunted with contemporary airguns, but having recently acquired a circa 1968 Webley Mk. III underlever from my good friend, Jack Stanton, I've decided to put such claims to the test.
To many airgunners of the 1950s and 60s, the tap-loading Mk. III is held up as the 'ultimate' of all sporters - moreso than its BSA underlever rival, the Airsporter.
Mine - serial no. A625 - is a .22 and is certainly extremely accurate over my 15-yard garden range. Considering its age, the tap has a fantastic air seal and the trigger is very sweet; 19mm groups are quite achievable with the open sights - although there's also a scope rail should I need a telly to maximise accuracy over longer ranges.
I haven't chrono'd the rifle yet - but it 'feels' to be doing in the region of 9 or 10 ft. lbs.. I'll let you know of the outcome if I ultimately decide to take it into the hunting field. (Which I do expect to being doing. After all, the Mk. IIIs that Webley produced between 1947 and 1975 must have accounted for a huge head of UK vermin. Even if the ratio was one kill to one gun, it would be in the tens of thousands!)
Watch this space...