Custom Yoke stretcher

[357454]

Thanks to this forum I contacted a local gunsmith for assistance with replacing a firing pin bushing in one of my competition guns. While IU was there he showed me a Yoke stretched he built in the 80s, I mention while I was leaving the if he ever wanted to sell it give me a call. A few weeks ago I received the call and purchased it. One of the main features over the modified pipe cutter sold by Brownells is the grove that is put in the Yoke body is round, chances of cutting the yoke in half are almost impossible. I slowly lengthened the Yoke on a gun I am rebuilding and found I was able to increase the length by a thousandth with little effort. If possible I will post pics. By the Way the stretcher was built by Paul Smeltzer, Paul mentioned he has the original plans on Auto Cad!

 

[Protocall_Design]

I have one from Brownell's made by Wessinger that looks very similar. I made the wheel with a flat rim. It makes a flat ring that is very shallow, even stretching up to .005.

 

[LAWMAN662]

please enlighten me

please enlighten me; what is purpose of stretching the yoke? new to me.

 

[ViperR]

Same purpose as adding shims to eliminate excess end shake.

 

[357454]

Stretching the Yoke

The main reason for stretching the yoke is to correct excessive end shake (cylinder lateral movement). I set most of my revolvers up to have about .001 to .002 end shake. This will eliminate friction resulting from the case rubbing on the breech face, (too little end shake), or the end of the cylinder rubbing the end of the barrel (too much end shake). A secondary benefit is more reliable ignition when the headspace is too wide.

 

[Nightowl]

That is really neat. The pipe cutter one is awkward for me to work, and the cutter I bought from Brownells has a sharper edge than the one from the original kit that somehow got lost many years ago.

That looks like it could be expensive to make.

 

[chief38]

The Yoke stretchers work OK, but now that the old Smiths are suffering from expensive and harder to find original parts I much prefer the stainless steel shims that Powers sells (Brownells and Midway should have them too). Not only are the shims easy to install but they can be custom fit by using as many or as few as required. If you put in one too many, just pop it out and try again. They are also available in two different thicknesses which allows a custom fit in seconds.

Remember once you "stretch" metal by cutting a ring, it weakens it somewhat and it can change again under heavy usage more easily than when it was at full thickness. PLUS.... the Shims do NOT require any special tools and skills which is much better suited for many who are not experienced with working on guns.

 

[ViperR]

TriggerShims Brand Shim Kits

A better place to get them. Free shipping and outstanding service.

 

[chief38]

I have also made a few from Starrett Shim Stock with punch cutter set. Not a big deal to do.