In this summer's X-Men Days of Future Past, director Bryan Singer confirmed that the past timeline version of Wolverine will not have adamantium claws since the Weapon X program has yet to take place. Meanwhile, fans have been wondering if Logan's future timeline version would have bone or adamantium claws. With the release of a new Empire Magazine cover of the future timeline version of Wolverine, see image above and full image below, it has been confirmed that Logan will have adamantium claws.
How this happens will most likely be a mystery until the film releases on May 23 or Singer reveals it beforehand. Until this happens, many can speculate that Magneto helps Logan reacquire his adamantium claws but this may not be as easy as many think. Being that this is a fictional metal any story can be made up about adamantium, but movie fans should already know that this metal can only be manipulated when in its raw liquid form. Note: Yes, Magneto pulls off Wolverine's adamantium in the comics but this is the movie universe.
Again, anything is possible when talking about a fictional metal. And it's in the opinion of The Daily SuperHero things that occur in the past to change the future timeline of the film are made so Wolverine never loses his claws in a battle with the Silver Samurai. Because when you change the past, the future changes as well. (To reiterate, that was all opinion not fact or a scoop.)
Regardless, fans will have to wait to find out but it is also important to note that they will also see the bone claws for most of X-Men Days of Future Past since Singer said approximately two-thirds of the film happens in the 70s timeline.