I'm no ballistics expert but by thinking about the physics behind it, I'd say that with all things remaining constant and varying weight of the bullet will not affect recoil in any significant way. The initial inclination is to say that the recoil will be more with the heavier bullet because for every action there is an equal and opposite reaction. That means that to move a heavier slug, recoil will be increased. This isn't necessarily the case because there is another variable in play. On my Desert Eagle, it has 6" in which to accelerate the bullet. Holding the powder constant in the equation, the heavier bullet will not reach the same muzzle velocity as the lighter slug. So recoil will likely be the same. If you were to use a heavier slug and more/different powder in order to reach the same muzzle velocity, you would definately have more recoil.
So to answer your question. I believe that recoil will be about the same regardless. Changing the slug and keeping all other factors constant, the recoil will not be more, but muzzle velocity will suffer.
That's my story and I'm sticking to it.