I have a question. Yesterday i was at the bow shop and was getting some new arrows. I told them to weigh the arrow and match up the weights. My arrow weighed 376gr with a 100gr muzzy,asked me what poundage i was pulling which is 68 and they verifed that on a scale. They advised me to get heavier arrows and said what i was shooting was almost like dry firing my bow. Is this true or not?