Mini barrel-cylinder gap?

[bearcatter]

Has anyone ever checked the gap? I can't find it stated with specific numbers. It's a big deal with some people in their normal sized revolvers. It's not considered as important with rimfire calibers.

It might be hard to check on a mini? How much space is between the top strap and cylinder pin? From forum photos, it looks like a standard 1/2 inch blade might slip in.

In serious target guns 2-3 thousandths is thought ideal. Four to six is typical. Seven or more is loose. All my revolvers are 3-5 thousandths. You measure it with the cylinder pushed forward.
There's another measurement called endshake, You measure that with the cylinder pulled back, and subtract the gap measurement. Example: .006 pulled back, minus .004 pushed forward, equals .002 endshake. Endshake should be less than .007. My guns are all .003.

[Rick_Jorgenson]

Great info bearcatter. I've heard those terms but was never sure how they were measured or what acceptable tolerances were.

Now, to look for some narrow feeler gauges and check a few Revolvers!  (Added to my list of things to get done.)

By checking while cleaning them regularly, this would be a good way to see if one was starting to get out of spec's from use or a change in ammo maybe affecting wear and tear. 

Early detection before failure.

[bearcatter]

I've edited my first post. I goofed. I just checked my gun box and my gun gauges are standard 1/2 inch.

How much space is between the top strap and cylinder pin on a mini? Looking at forum photos it looks like a 1/2 inch wide blade might slip in.

Gauges that go thin enough, or don't skip some needed thicknesses, are a little harder to come by. Ace has a couple like mine. .0015 to .035 and only skip a few of the thickest.

I didn't pay it much attention, until my first Single-Six, bought new, was spitting to the sides. The gap was .013. Ruger re-barreled it and cleaned up the trigger as a bonus. It came back .004.

[grayelky]

I have a Single Six I bought in 1971. There is no way of estimating how many thousands of rounds have been fired through it. I will have to check some measurements! The good news is, I have not noticed a difference in it hitting where I?m pointing. Not yet, anyway. Thanks for posting this.

[bearcatter]

From what I've read, .22 LR has little or no effect on the gaps, and .22 WMR would probably have minimal wear over time. It's good to check on a new revolver, just to be sure everything is as it should be. I would imagine that with NAA's use of CNC machining, and good QC, all their gaps are good and within a thousandth of each other. I was just curious as to what their standard gap is.
When I returned my .013 Single-Six, Ruger told me their QC allowed gaps as large as .010.