I have a few of these. I used one to open up a 223 bolt face to magnum. They work. But the stock extractor usually does too. Are you trying to repair something? If you keep the same bolt face then when you remove the rem extractor there's a hole to fill. If you get a bolt from ptg then you can spec this type of extractor in the first place. These guys have a good reputation too:
https://www.longriflesinc.com/produc...n-to-m700-bolt