Odd timing issue with Pietta Colt

[Columbus]

Recently picked up a Pietta Colt clone, date code 1995, came in a Cabela's box and looks almost new. Seemed to function just fine but was a little gummy from old lube and I broke it down, cleaned it all up and when I went to put it back together the bolt wasn't dropping at half-cock. WTH? Took all the parts outs and put it back together three times with the same outcome. Tried it with just the bolt in place, loose spring, tight spring and everyway I could think of and it might work once or twice but then would hang up. Got frustrated, pushed the bolt down, put the cylinder back on and put the gun together and now it works just fine. Cylinder rotates easily, locks up as it's supposed to and I've cocked and released a few dozen times and it's functioning well. Only thing I can figure out is that the bolt must be overextending when the cylinder isn't there and then it's out of position for the cam. Does that make sense, has anyone else had this happen?

 

[nkbj]

Yep, on a new Pietta brass frame "1860".
The side of the spring that pushes on the cylinder bolt is just a little bit shorter than it should be. To get it properly re-assembled without the end of the spring slipping off is a real booger.