A local gun shop/range (that has not demonstrated competence with revolvers) has informed me that two of my revolvers are "out of time" and therefore unsafe to shoot. I asked them to show me. This is what they did...
- Cock the revolver.
- With the hammer back, attempt to turn the cylinder right and left.
- There is some noticeable wiggle. Not much, but you can see/feel the wiggle. I measure the wiggle at approximately 0.5 mm (holding ruler next to cylinder as I wiggle it).

What is the proper term for this wiggle?
What is the acceptable tolerance for this wiggle?

Thanks,
--Joe.

PS: One of the revolvers is a .38 M&P from 1920. Caliber marked on barrel is "38 S&W Special CTG". Clerk at gun shop told me that this is not the same our current .38 Special, but an older fatter obsolete round - he was clearly confusing this with .38 S&W. So now I don't believe anything they say.

You do want a wee bit of possible "wiggle" to allow the cylinder to be able to move slightly should there be a slight misalignment between cylinder chamber and barrel.

"Out of time" is a phrase widely misused. I wouldn't let them fondle your firearms in the future.

My instructor at the armorer's school, John Contro, called it "wink". As long as the gun meets factory specs regarding carry up, and the stop holds, this wink or "gauge" on the stop is perfectly normal, in fact, desirable. Gauge felt in the movement of the assembled parts includes the necessary space for the stop ball inside the stop slot, and the cylinder stop's "wink" in the stop window in the frame.

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Ret. LE, FA Instr, S&W Armorer

Joe - interesting story – not many ranges in NoVa so this may have been Sharpshooters or maybe even Elite Sports. I haven’t seen anyone, at either location, who looks like a revolver smith! First time that I have seen or heard the term “wink“ but all of my S&W’s have it and all shoot just fine with no issues. Not that I own one - but I think Pythons were fitted such that they did lock up tight ...

Saying that they had "not demonstrated competence with revolvers" is, in my opinion, a VAST understatement!
Were I you, I'd pick up my guns and never darken their doorstep again.
IIRC (and if I'm mistaken someone please correct me) the method they're using to "show you" is used solely on Colt's revolvers to judge lock up and pawl ("hand" in S&W terminology) wear, and has ZERO to do with demonstrating proper carry-up (timing). This method shows you NOTHING on a Smith and Wesson other than that it's actually locking up and the cylinder stop is actually working. A touch of wiggle is dead normal, and as others have stated desirable. I'm unaware of an actual "spec" for the amount of wiggle. Perhaps someone more knowledgeable will come along with that info.
Wow! The fact someone would misrepresent their knowledge of a firearm to sell service on said firearm blows my mind!
I wish you well!

This is a common misunderstanding of how different brands or revolvers work.

Timing is the process of a revolver cylinder unlocking, rotating to the next chamber and re-locking.

Lock up is how the cylinder is locked in place at the moment of ignition.

Alignment is the centering of the chamber with the barrel.

In the old Colt actions as used on the Python,Detective Special and the older models when the trigger is pulled the hand pushes the cylinder into tight lock up. This was known as the Colt "Bank Vault" lockup.
The harder (within common sense) the trigger is pulled the tighter the cylinder is locked.
With the trigger held back an old Colt action should have zero cylinder rotational movement.
In the old Colt's when the trigger is pulled the cylinder is forced into perfect alignment with the bore and tightly locked there.

S&W, Ruger, Dan Wesson, and the later Colt revolvers like the Mark III, Mark V and others all work in an entirely different manner.
With these revolvers the hand does not continue to push the cylinder with the trigger pulled.
The action is deliberately designed to allow some slight cylinder movement when the trigger is pulled so the bullet passing from the chamber to the barrel will force the chamber into alignment with the bore.
This eliminates the extensive hand fitting needed for the older Colt's and lowers the cost to build the gun.
Virtually all modern double action revolvers work this way.

So, the only modern revolvers that will lock tightly with the trigger pulled are the older Colt's.
The S&W and others are designed to be slightly loose with the trigger pulled so the bullet can force the chamber into alignment.

How much rotational movement is acceptable is not a S&W specification.
The only standards are.... Is the revolver accurate? Is the revolver spitting bullet metal out the barrel-cylinder gap?

If the gun is accurate and not spitting bullet metal it's good to go.
Of course a badly worn revolver will be much looser and might benefit from maintenance.
Even if a S&W seems to lock tightly there's still enough backlash designed into the action to allow the necessary cylinder movement at ignition.

Let me give you a bit of info on the .38 S&W. The .38 Special projectile is .357" while the .38 S&W is .361" The overall length (OAL) of the S&W round is much shorter than the Special, therefore, a Special will not fit the cylinder chambers of a .38 S&W. Some folks have had the .38 S&W chambers reamed out to accept the .38 Special but then have problems with cases bulging when fired and etc. I have to agree with some of the folks above, that many times clerks at gun shops are not too knowledgeable when it comes to the mechanical meshing of parts in a firearm.

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Ed

Colts lock up tight.
Drew the hammer back ever so slowly and only one Diamondback out of many was the birthday gift for the Mrs. decades ago.
Timing nerd?

Thanks for the replies.

So what's the gun shop name ?

John was my instructor also and he surely knew S&W revolvers and I recall the ‘wink’ from my notes. As noted, you have to have some ‘wiggle’ / ‘wink’ for the revolver to work properly.