The cylinder usually only spins in one direction when released, although a single action can be altered to spin in either direction for ease of loading.
Before I discovered wax bullets, now and again I would occasionally get a bullet stuck in the barrel when I shot indoors. My solution was to fill the length of the barrel behind the bullet with water and fire a primer over it. The primer creates little pressure and the water is not compressible so more often than not the bullet drops out on the floor. I have stuck them hard enough though to where I have had to repeat the procedure several times to get it to work. I have done this with both revolvers and pistols with no ill effects whatsoever, and there is no chance of damaging the crown or bore. If you insist on pounding out the bullet, a wood dowel of the correct diameter might be a better choice than a metal rod, particularly if a soft metal drift like brass is not available.