I've a std Hw100 (.177) and use JSB heavies. I get 9 full magazines per charge, that's 126 shots...
My previous two full length .177 models would do 140+ shots per fill,with my latest doing 136,all with JSB Exacts.
My carbine 4 mags 56 shots jsb exacts
IIRC Fluffy a member who I haven't seen on here for a while,
He totally stripped and reworked his K getting it working at optimum.
He got nearly full length shot count from the K and I would totally own one if I could do this.
Master Debater