Bind skeletal mesh bone to another skeletal mesh's socket? (pulling a bow's string)

I’m trying to do a bow pull-back, and I already have the bow rigged and everything, I just don’t have the pull-back done yet. Previously I had an animation play on the bow, but since you can create characters of different proportions the animation became inaccurate, so I’m trying to see if I can just dynamically snap the string on the bow to the character’s hand. Anyone know how I can do this?