It's not that difficult a problem and you can work through it yourself. There's a lot of info available out there or you can get some from a shop but even then if you don't know what is what you won't know if what you are being told is right. For example I went to a very popular shop yesterday owned and operated by a national bow champion looking for some things. The young man there kept trying to sell meX when I kept asking him for Y. He honestly didn't know the difference.
There's a site out of the UK that I turn to for help. It goes by the name of Alan's archery.
Good luck andjust be patient. Dues mst be paid.
