my bow is supose to have a 65% let off but when i went to the range and checked the draw is said 65lb. max and then i checked the holding wieght and it read 15lb. whe comes out to 85% i aint complaining, but how is this possible?

So that means the bow is holding 50 of the 65 total pounds of the bow? If that is so, then that is around 77% let off.

What kind of bow do you have, I know with my bow you can adjust the let off percentage with the cam from 65 to 80, if so look at the cams there my be a way to change it. That is really all i can think of.