Two jumps for me:
1) bone claws (x-men 25/wolv 75)
2) Origin/James Howlett (I feel like a tool just typing that name!)
The story of X-Men Vol 2 #4-7 is only about badass Wolverine fighting badass Omega Red with the other X-Men around as sidekicks & spectators.
Back then, everybody bought the book because Jim Lee was the most popular penciller of Marvel Comics.
John Byrne is a good writer but, curiously enough, I didn't recognize his style. I am not certain that he contributed a lot to the story.