revolver head space

[Patrick1981]

Hi guys

After reading the Jerry Khunhausen book of revolver..I think develop why in my 686 SSR I can't have a trigger job well as on my old 686-2 and 686-5.

I read the correct headspace is not lower than 0,060 and not over 0,064.

Lower do bind and much cause mistfires.

( In mm. is 1,52 e 1,62 ) In my SSR I can put also 1,65 mm.

Probably the best and resolutive way is change revolver.

But for you there's any mysterious way to make something to reduce headspace of 0,10 mm. (0,004") and not enlarge cylinder gap ?

Thanks for the miracle

[Toolguy]

You can put a .004 Power custom endshake bearing under the extractor. If the cylinder has no endshake now, you will have to turn .004 off the round part in the middle of the ratchets to allow the ratchets to go further back. If you do that, turn the ratchets down .003 below the new surface so they don't drag.

Personally, I wouldn't worry about it. 1,65mm is only .065. If you want to make the firing pin longer to make up for more headspace on the guns with a firing pin on the hammer (hammer nose), you can punch the FP pivot pin out, take off the firing pin and spring and grind the face of the hammer .005 - .010 being careful to keep the original angle of the face. Then put the firing pin back on, restake the pivot pin and the firing pin will stick out further by the amount ground off the hammer face. On the newer guns of course it's easy to just put in an extended FP.

Any Smith Revo can have a great action if you know enough tuning secrets.

There you go - 2 miracles!

[Patrick1981]

You're a Master! Great ideas!

No, I can't have endshake now (but I have install a 0,004 to eliminate that 2 years ago)

I use an Extended FP and a reduced FP return spring but since from the beginning I never have great result like on the others Smiths.

In this days I analized more detalis and I see the face of the yoke crane is not perfectly square.

I use a black paint pencil on the face, put inside the cylinder and run, put back and the black is gone only from 3/5 of the face. Is this another possible cause?

The alignment seems good, open and closed smoothly.

Thanks Warren.

Edited June 10, 2013 by Patrick1981

[Toolguy]

What is the exact problem you are having? Misfires with a light trigger pull? You must have a minimum force on the hammer to be reliable, then all other lightening must be done somewhere else, mostly in the rebound, but also making sure nothing drags even a little.

I always make the back of the yoke square, then stretch the crane to remove endshake. You can add washers in place of stretching. There is a good Power Custom tool for squaring the yoke. It will develop endshake sooner if the yoke is not square.