www.makemkv.com

If you need to use MakeMKV but your legally purchased BD disk is defective, you might want to try going to your local library and see if they have your title on BD. You can check it out and use their copy so you don't have to purchase another copy. It's probably free to check out of the library.

Technically, that is more illegal than making a copy of a disc that you actually own, but yeah no one's ever going to know that a copy has been made!