View Full Version : Cylinder/barrel gap

June 16, 2006, 01:44 PM
What should be the correct gap between the cylinder and barrel on a High Standard .22 revolver?
It is less than .0015" at present and after a few shots goes to zero and locks the cylinder.
Thank you.

June 16, 2006, 06:34 PM
Almost all revolvers work best with the same barrel/cylinder gap of from a minimum of .003 to a maximum of .012.

About .005 is about perfect.

The barrel/cylinder gap is cut with a special tool that puts a rod down the bore, and has a flat faced cutter that screws on the end.
The rod is pulled toward the muzzle and the rod is turned, cutting the end of the barrel.

Once the barrel/cylinder gap is set, the forcing cone MUST be re-cut and lapped with another special cutter and a brass lapping head.
The forcing cone is CRITICAL to accuracy and the outer diameter of the cone is what's important.
This CANNOT be "eyeballed".

To gage the cone, you use a special plug-gage that drops into the forcing cone and gages the outer diameter.

I'm saying all this to insure you know not to allow some "gunsmith" to use a file to hack off the end of the barrel and call it good.
The end of the barrel MUST be cut absolutely square with the bore, and NO ONE can do it right with a hand file.

Failing to properly cut, lap, and gage the forcing cone will produce a gun that's inaccurate and spits lead.

June 17, 2006, 09:17 AM
Why not chuck up the cylinder and face it off a few thousands where it interacts with the end of the barrel, then deburr the ends of each chamber?
This would not alter the end of the barrel.

June 21, 2006, 08:28 PM
I have a High Standard Double-9 that had the cylinder bind after I had it for several years. The problem turned out to be leading and some sort of fouling in two places, on the face of the cylinder and between the barrel and top of the frame, curving around onto the end of the barrel. Simply removing the fouling cured the problem.:D

Try doing a thorough cleaning of the cylinder face and the rear of the barrel. Be careful not to use any harsh materials that may scratch either of the parts. There are several products on the market that will help remove leading but start with normal powder solvents first, such as Hoppe's #9 or equivalent.

Perhaps someone else on this forum can suggest something better to remove leading. I did this so long ago that I can't recall details. With careful cleaning after firing, the problem has not recurred in my case.:D :D