bronco73

My brother has a 2002 Mathews Legacy bow. He shoots a 20-40 times every day. He had a failure in one of his limbs splitting. Mathews went ahead and replaced it, at the shop he purchased the bow from. He then felt the bow had gotten a little load, which he had not noticed before. He was told it could be his string. He was told the fibers in the string may have stretched or broken. He went ahead and had the string replacved bya Winners Choice string. The noise quieted down. He also ad the bow tuned with the new string, cam timed, and peep sight set, etc. Here is the problem now, the bow groups really well out to 40-50 yards or so, this is not a problem. My brother is a very good shot, and routinelyshoots a grapefruit sized group at 40-50 yards. He has noticed that one day the bow shoots great, the next day it is 6.0" high at 20 yards? At first he thought it was in his head, that he was doing something wrong/differently. The next day was the same. He thought maybe it was because he left the bow in the sun, and everything got hot and expanded/stretched. (BTW, He has put at least 200-300 shots on this new string.) He ended up adjusting the sight, and this cured the problem, until today. He just called and said the bow is now 6.0" high again. What is going on? I told him to double check that everything is tight. Do any of you guys have any guesses at what it could be? My brother is thinking of just starting over, and buying a new bow, this is how frustrated he is. I know he is shooting the same, his grip is the same, his stance is the same, his face and bow string contact is the same, his release is the same. HELP!