In SWEFTA we run an annual league FT series and an annual league HFT series.
The FT shoots are graded, whereas the HFT shoots are not.
To determine the winning club at the end of the season, in FT we just take the best three scores for each club at every shoot and add them up. The HFT works slightly differently and is a kind of handicap system. As we have only one HFT champion club, and some folk shoot PCPs and others shoot spring guns, we needed a way of merging their scores together that recognised the slight disadvantage for the spring gun shooters. So what we have done is to add one point to a spring gun score for every ten targets on the course.
Example; a 30 shot course, someone shoots say 54 ex 60 with a PCP. Another person shoots a 52 with a spring gun. 30 targets means 3 bonus points so the spring gun shooter gets 3 added to his or her 52, making 55, and beats the 54 with a PCP.