I know this maybe a stupid question however I need to ask. When I see the Grains Per Inch "GPI" on an arrow shaft for example my ICS Beman Hunter Pros are 8.8 GPI. Is this GPI weight Including the nock, insert and fletching etc? Or is the 8.8 GPI based solely on the arrow shaft alone?

GPI is shaft alone. You'll have to add your nock and ferrule weight at each end, and any other item you install (pin nock insert, point, fletching, arrow wrap, paint, nock weight, tip weight, etc...).

Nomercy thank you!