I have an 1851 Navy. While I've had problems with it in the past I had it working well for a while. When it was first given to me the bolt-trigger spring screw was too tight, this prevented the cylinder from rotating on half-cock. After I adjusted the screw holding in the bolt-trigger spring the gun functioned flawlessly. I shot, cleaned, and reassembled the gun several times after this without issue. Recently I shot the gun, cleaned and put it back together. I noticed the cylinder wasn't rotating properly. I went about adjusting the bolt-trigger spring screw until the proper function was reached. I've done this several times and I've always been able to find the sweet spot where the cylinder could rotate without issue. This time nothing worked. If I tighten the screw too much the cylinder won't rotate on half cock. this also makes the gun feel very tight. If I loosen the screw the cylinder will rotate freely on full cock or will even rotate in the wrong direction. Even turning the screw a little at a time doesn't work. At best I get stuck with one of the two situations from before. At worse I think I fixed it. I rotate the cylinder on half cock and it holds on full cock, only to rotate backward or on full cock after I think the problems are solved. I bought a new mainspring, bolt, and bolt-trigger spring. Even with the new parts, this problem has persisted. To keep the gun safe to use I keep the spring screw tight. I don't have any more experienced people to go to for advice. Does anybody have a way or idea to solve this?

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P.S.: I would like to reiterate that I have used, cleaned, and put this gun back together before this problem without issue.