Thanks for the reply. I am an inquisitive type and never noticed this change before. The bolt head looked odd with the oval shape. I knew Remington went to a rivetless extractor many years ago, around 1980 I believe, but I did not know Remington changed the way they machine the bolt head to fit the new extractor. The new extractor must work fine, because I have herd very little complaints about them failing. Again thanks for the info. Just wondered.