I would get his whole routine a L. more in order and then do CIO. When my first daughter was that age, she would NOT sleep at night, and she would sleep all day. The Sleep, Eat, Wake cycle saved us and got her in a rhythm, and soon after she started sleeping at night instead of day. Maybe the rhythm would help your son make his own adjustments. Feed him as soon as he wakes up from any sleep, then let him play a bit, then let him drift off without eating until this is a pattern. YOu can still feed him before bed time though. Also, be sure to feed him to absolute capacity during the whole day, even if you think he's full-offer more feedings. By about 6 months, if he's eating enough, he's well capable of sleeping through the night.
I would stop all the swaddling and soothing at that point, because he is already screaming because he wants it. We walked away from the start with all of ours so they didn't get used to anything but their own sleep comfort, but he can still learn to sooth himself if he doesn't think you will come in to nurse, swaddle etc. It will take a few nights for him to really get it that you're not coming in. Giving in at his most hysterical has taught him that if he cries long enough and get hysterical enough, you'll come in and save him. Don't worry, he can break the habit.
See if there is a way to make his crib more comfortable-my 3rd would roll around and wake herself up a lot on a firm pad, but slept like a baby when I softened up her cushion a bit. Is there anywhere in the house-your bead spread, a certain blanky, a car seat, where he seems to fall asleep the most? try to reproduce that surface in his crib if possible. Adjust his routine, then feed him more then CIO!