Here's what my husband and I did with our son, who was about 5 1/2 months at the time. When we did this he was waking two to three times per night to nurse. I started reducing the amount of time he nursed every night ( you could do every other night if you would prefer, it will just take a bit longer) So if you have been nursing for 6 minutes, only offer 5 1/2 minutes of nursing tonight. When there are multiple feedings per night, you also increase by 15 minutes per night, the amount of time between feedings. So you would do 5 minutes of nursing every 4.25 hours tomorrow, 4 1/2 minutes every 4 1/2 hours the next night, and so on. We found this method in Dr. Richard Ferber's book (which made a lot of sense to me, you may want to try reading it to see what you think), and it worked really well for us. Since you are bottle feeding, you just gradually reduce the amount in the bottle, 6 oz. tonight, 5 or 5 1/2 oz tomorrow etc. According to the book, most kids stop waking to eat before you can reduce them down to nothing, my son stopped waking to feed after 4 or 5 nights. I thought a gradual approach was better than just trying to quit cold turkey, which seemed pretty awful to me.
Also, make sure when you go in to feed him, you keep it as utilitarian as possible, no lights, no conversation, just nurse and back to bed. You want to show him that nighttime is for sleeping.
Best of luck!