In 8 months I went from 175-180 range to 200lbs. I am 6'1". I did get a bit more of a gut doing it, but you have to eat to gain.
I was lifting 5 days a week, sometimes 2 times a day for 6 months straight. I still mixed in some cardio as well.
I would have 5-6 protein shakes a day, 2 of those being CytoGainers. The other 4 were Syntha 6 or Muscle Milk.
I ate 5 times a day. I did all this for almost a year just to gain that bit of size. It's hard work, really hard. And it gets expensive for protein and food. As I tell anyone trying to gain size, lift more, eat more, sleep more.
If you think you're lifting heavy, get a spotter and lift more. Lift till failure, drink protein, eat a lot. If you think you're getting fat in the gut, eat lean meat, alot. You can cut back fat once you reached your gain goal, you HAVE to eat, mass cannot grow without an excessive calorie intake.
And the worst part about it all is that it will all go away really fast when you don't keep up with teh lifting and eating. I am back down to 185. I'm not lifting as much anymore