Hi
this is from the BSA forum a post made by Tench a very knowledgeable person on airguns
i found that the BSA barrel rarely needs cleaning at all, some other makes of barrel go off after a few hundred shots, a good pull through gets them accurate again but the BSA barrel with the JSB heavies never went off. The ft/lb advantage they have is huge too, at 50 ish yards they will have 1.5 ft/lb more than the lighter ones, its like tuning your gun! The pellets wide waisted design is the key feature, this places more of its mass away from the centre of rotation, this produces more flywheel eff