OK, so I just filled my M/C with brake fluid.

Check this out, it should explain a lot:  

http://www.youtube.com/watch?v=i3Jhbz4mVKw

I have used pressure and vacuum successfully I usually use vacuum on my American cars and pressure on my foreign (no reason other than I have a pressure bleed adapter that fits BMW and jaguar and don't have one for older Chevy master cylinders) You can buy a vacuum bleeder kit at autozone for about 20$

Also Did you bleed master cylinder before connecting lines?

A pressure bleeder will get the air out of the master, if it wasn't "bench" bled before installing it. I'm not all that hot on using the vacuum bleeders for anything other than getting the fluid down to the calipers....after that, it's time to really bleed them. Using the vacuum pumps(MityVac, etc) can suck air back into the calipers past the seals if yer not careful, so ya gotta watch it.
Joe, you prolly need to bench the master before going any farther. As is shown in the vid that Larry posted. Of course, it's easy if you don't have a car on top of the master, like that guy had! I usually put my masters in a bench vise, attach the vinyl hoses to it, and then use a large screwdriver to push the piston in/out, until there is no more air in the hoses. Yo can do it on the car if you have a helper, but....you're taking a chance on some of the brake fluid getting all over your nice fresh paint...
Gravity bleeding has never really worked for me...in order for that to work, you need to have fluid in the lines to start with. If the master wasn't bled first, it'll never happen.
Even WITH a pressure bleeder, I have to go around ALL of the bleeders at least 3 times to be certain all of the air is out of the system.

Guys,

Cover OFF on the master for the vacuum bleed. Be sure not to draw too much of a vacuum at first...too much, and all you'll be doing is sucking air past the seals. Just pump it gently, until you see fluid coming thru the hose.
Start at the right rear, and be sure to do BOTH sides of the rear calipers...starting with the outer bleeder first...then the inner. Then move to the left rear, then right front, the left front.
hth.

I have a vacuum bleeder and it does pull air into the calipers..I put an adjustable pressure regulator on it to knock down the air pressure down to 25 psi..it works then..leave the cover off the master when you do this and stay close to the master cylinder too as it will pull the fluid thru real fast once the fluid starts moving..once you get the fluid at all 4 wheels then pump the brakes to manually bleed them to finish it off..do this part with the cover clamped down on the master and keep an eye on the fluid level..it doesn't take long once you get the fluid moving..its just getting it to that point!

Cool guys.

Here's a pic of the pressure bleeder I made: