As far as sex being only for procreation, this is most certainly wrong.
Quote:
1 Corinthians 7: 3The husband should fulfill his marital duty to his wife, and likewise the wife to her husband. 4The wife's body does not belong to her alone but also to her husband. In the same way, the husband's body does not belong to him alone but also to his wife. 5Do not deprive each other except by mutual consent and for a time, so that you may devote yourselves to prayer. Then come together again so that Satan will not tempt you because of your lack of self-control
If having sex with your wife while not trying to have a child was I sin, I think that I would most certainly be going to hell
As far as masturbation, no there is nothing in the bible that says anything against it specifically. As I believe someone pointed out, if one was to think about his wife, or possibly someone (if that person was not married) in a "marriage" situation, it seems to me to be perfectly acceptable.
I would be more than happy to look at any biblical evidence to the contrary. So far no one has presented any.