Hand/Spring Colt 61 Pietta fitted but indexing not perfect

[Sundance]

Well after 3 hrs of trying to match the old hand nearly got it right.  BUT sometimes the cylinder will not lock up.  Cocking action a lot stiffer as well, I reckon I just need to fettle the face of the hand a tad more.  What do you guy's reckon?  Prior to the spring breaking the action was perfect so assume the hand is the problem.
Could someone give me a description of what the face of the hand should look like?  The old one went to a point -  angled from the left hand - side.  Hope that made sense.
Thanks fella's

[Fox Creek Kid]

Maybe I'm misunderstanding you here, but if the hand spring broke simply drive it out & replace with a new one as there is no need to replace the entire hand. 

[Sundance]

Thought of that Fox, but looks a swine to remove what is left of the old spring and then take the spring out of the new hand/spring.  You don't seem to be able to just get the spring on its own in the UK.
If I still can't resolve though this might be an avenue I will explore further.  I must be close to getting it right as sometimes it indexs perfectly.
I appreciate your response any comments or ideas greatly appreciated.

[Coffinmaker]

Sundance,

Tough to give you a "what it should look like" description, because each hand if fitted individually to the gun.  Except as they come in the replacement package,  no two look the same.  Also depends on the preference of the build-up tech in italy. 
Usually, I get it close to what the original looked like, if the original worked correctly.  If not, I start with the hand long and just "fit" it to the gun until it indexes like it should.
Key word here:  Patience.
While you have the gun apart, also check the fit of the bolt to the locking slots in the cylinder.  On quite a few Pietta I've had in the shop, the only reason they worked was because everything came to a stop in alignment.  The bolt didn't really drop into it's slot.  Something to look at.

Coffinmaker

[Sundance]

Yep, your right there PATIENCE is the key.

Well stripped it down again - I can do this blindfolded now I reckon, and just gave the face of the hand a tad of a file, also went around the sides.  I put it back together and of the opinion thats as good as I'll get it.  Its now indexing fine except on one chamber its slightly harder to cock, its indexing though just stiffer.  I have the feeling that with use it will bed in so for now leaving it alone.

Fit of the bolt in the locking slots appears fine Coffinmaker no signs of drag on the outside of the cylinder either is that what you meant?  Cylinder is locking up fine.

Do you think I should leave it or fettle some more???

[Coffinmaker]

The way a gun works "on the bench" and "at the range" can be somewhat different.  Time to start shooting it.  If you have one chamber that is "stiff," you may have a "high" spot on the star (ratchet at back of cylinder) or a "high" spot on the cylinder face, either of which is dragging as the cylinder turns.  Shoot it a bunch and then look for a shiny spot at the star and check the front face of the cylinder for scuff marks.  Sometimes you get both.
Don't be stingy with the grease on the mandrel either.

Coffinmaker

[Sundance]

Prior to stripping it again sat down and rotated the cylinder for a few minutes on half cock, tried it again and seems PERFECT EVERYTIME so consider it FIXED...........AHHhhhhhhhhhhh successssssss.
Many thanks guy's for your wisdom.
Coffinmaker - perhaps the grease went to where needed??? - again many thanks.  When it breaks again I'll know what to do.