One thing to remember is Calcium itself is a 'Metal'.
Over the years, Marvel has shown Wolverine's skeleton as having adamantium as strips and leaf. The most prevalent as seen in the original 'Weapon-X' and 'Wolverine' comics, is the indestructible metal being force injected into his bones not as a thin layer.
In his early appearances of the revamped X-Men comics, Wolverine's claws were said to be 'Bionic' additions. It wasn't until many years later in the X-Men comics it was revealed his claws were natural after Magneto pulled the Adamantium out of his body (BTW I always thought was impossible since if it's indestructible, then it can no longer be manipulated at least by a non-cosmic-class entity.)
Following the force injection theory, then that's where his original Calcium bones come into play. Calcium bones are densely packed crystalline structures with a spongy bone lattice at the core. Force injection theoretically could fill those spaces within the dense section of the bones. Where the prospect totally falls apart is first, the metal would have to be so hot to remain liquid it would be seriously unlikely Wolverine's healing factor could cope without serious deformities. Next, the adamantium would fill the space containing the marrow and healing factor or no, would destroy it. No marrow, no life. It is quite likely that bone marrow is the source of his amazing healing factor. Now, Marvel has said because his body is constantly healing the damage done by implanting the metal his HF is far less than it would be normally.
As an experiment, I cast a human femur in bronze. The one bone weighs 20lbs. Unless Adamantium weighs a lot less than bronze, Wolverine would be far heavier than 300lbs!
Really, what would cause him the greatest suffering would be the constant destruction of the bursa in his joints (the cartilaginous padding between bones.) Even if his healing factor could keep up with the normal everyday destruction of just moving, he would be in constant agony in training and laid low during a fight.
So with force injection being problematic, the only other options are having used a form of electroplating or Nanitic (using nanites) implantation.