I have both the HW45/Beeman P1 and the BSA 240 an they are in .177 cal. You are correct that the 240 is not as powerful as the HW45/Beeman P1. However it is very close. At least with the ones I have. My Beeman P1 shoots at about 540 fps with the light RWS Hobby pellets and the BSA 240 is just a bit slower at 520 fps using the same pellets. So that comes out at 4.53 ft lbs for the HW and 4.20 for the 240. I find the larger heavier 45 easier to shoot accurately as the smaller 240 has a bit more snappy recoil. That's not to say you can't shoot the BSA well I just find it takes a bit more practice. Both nice pistols.