My son was shooting Muzzy broadheads 75 grain until he got his new bow Bear Lightsout. His draw length went from 28 inches last year to 30 inches this year. He is shooting Axis ST carbons 400, I was told he needed to step up to 100 grain muzzy's due to his draw length and weigth of his arrow and poundage he pulls. The shop owner said we could get a 25 grain washer to add to the 75 grain broadhead but the arrow may not fly true. So I went and purchased the 100 grain broadheads. Can anyone shed some light on this subject is this true