I used to shoot on a farm years ago and would shoot 300 yards or more over a tilled field on a slight rise. aim for a clod of earth or stone with the barrel raised just out of scope could hit the same place quite often with a puff of dust from the strike, very satisfying, i once placed an old gramophone record out about the same distance which i could hit and could penetrate. I think the air rifle was a Webly Hawke .22 and a BSA Airsporter.
I was looking on youtube at slug shooting in South Africa using the FX impact in 79ftb, got me thinking using 12 ftb with slugs and thought that a light slug in .177 would be stable enough at .177 velocities higher than .22 and would be accurate at longer distances with the slug over a pellet, A company called Griffin do slugs in lighter weights at 10 grains. Any one tried Griffin slugs before.