Ruger blackhawk revolver-question:

[outdoorman]

I'm talking with a woman who will sell her ex's guns which include a Ruger Blackhawk revolver in .357 magnum.
I think the cylinder turned when I cocked before I took it out to inspect the barrel. But after replacing it, it woundnt. In fact, the hammer wont even cock back. Also replacing the metal rod into the cylinder was unually tough/as if tight fit.  How serious of a problem is this-will just some lubing solve this or is it an expensive fix. Incidentally, the gun was stored in a gun case and apparently not handled for some time.

[Savage]

They cylinder base pin is not properly installed. It must be seated all the way in for the cylinder to cycle. Push the release button as you insert the pin and make sure the cylinder is properly aligned. It should go right in. Sounds to me like you are not familiar enough with the handgun to be attempting to disassemble it. Might be a good idea to have someone more familiar with the gun reassemble it.
Savage

[Tom W.]

If it's a new model the hammer won't cock with the loading gate open.....

[bilmac]

Rugers have a habit of going togather with the base pin a little cocked and then acting like everything is jammed up. I hope you didn't try to force anything. What you have to do is to get the base pin back out. Hold the cross pin that holds it in place open while you do it. It will be hard to get out but that is what needs to be done. When you do get it apart, then put it back togather gently while you wiggle the cylinder.

[Savage]

If it's a new model the hammer won't cock with the loading gate open.....

But the cylinder will rotate freely if the base pin is properly installed. 
bilmac, Yeah the spring loaded cross pin, not the release button!!!
Savage

[blhof]

If the price is right; you can't go wrong with the Black hawk.  My son has one in 45 colt and it's a real shooter.  Ruger customer service is also hard to beat.  I've sent in an older single six and it came back looking like new, with only shipping charges.