I tend to agree with Brent, thejanitor. I too have shot thousands of rounds thru Handies, but not 2000 through one. While the hole was off from the begining, it did work properly for a normal lifetime of shooting. I don't know if Remington will give you any satisfaction on the issue, but it is worth a try.
Not that it is related to the problem, I was wondering what condition the barrel was in after that many rounds.
Good luck,
Pete