Very easy to fix. Take the bolt out and look under the handle. You will see a small indent on the underside of the bolt. It is where the bolt handle meets the receiver locking lug. Take the tip of the punch and tap it here in the indent. It may take a couple of taps but will tighten up the handle. This can be done on the 510,511,512,513,514 and 521 Remington rifles. Tim