You have to understand the mechanics of modern revolvers.
The only DA revolvers to lock up TIGHT when the trigger is held back, are the old Colt designs like the Python.
Colt was famous for their "Bank Vault" lockup, and when the trigger was held back the cylinder was immovably locked in place with ZERO movement possible.
In the Colt design, when the trigger is pulled, the cylinder is locked in perfect alignment with the bore.
The bullet enters the bore perfectly centered, and this means that there is no distortion of deformation of the bullet.
Since the bullet enters the bore perfectly centered and undistorted, accuracy is better, and this is one reason the old Colt design guns were famous for better accuracy than other designs.
The problem with this design is, the action MUST be hand assembled and adjusted to give that perfect alignment.
This hand labor raises the cost of the revolver to produce.
This is why only the Python is still made, and why it costs so much.
In addition, if the action does get out of adjustment, it simply stops working correctly.
In all modern DA revolvers, including the Taurus, the cylinder is deliberately designed to be slightly loose when the trigger is held back.
In this design, the slightly loose cylinder allows the bullet itself to align the cylinder with the bore.
Since this type action doesn't require extensive hand fitting to insure perfect alignment, it's much cheaper to produce.
The looser, less exacting design also means that the action can get slightly out of adjustment and still work properly.
The down side of this type of design is, since the bullet never enters the bore perfectly centered, the bullet does get distorted and deformed when it hits the barrel's forcing cone off-center.
This distortion slightly degrades accuracy, and so these designs don't have the better consistent accuracy the older Colt action does.
In short, your revolver is intended to have a slight amount of cylinder movement when the trigger is pulled.
There is no spec or standard as to how much is TOO much.
The tests are :
Is the revolver within specs for accuracy?
Only the factory knows what their specific standard for accuracy is, but the owner can determine if it's unacceptable to him.
Last, does the revolver spit bullet metal out the barrel/cylinder gap?
If the revolver spits, this is a sign of several possible problems, one of which is the cylinder being TOO loose, and failing to align properly.
Bottom Line:
If the revolver is reasonably accurate and doesn't spit bullet metal, the revolver is working properly, and how much free movement there is in the cylinder is not an issue.
