S&W K frame barrel / cylinder gap?

[velocette]

I have a very nice S&W K frame . 38 spl Target Masterpiece, 5 screw, made in 1954. (forerunner of the Model 14)
It's barrel / cylinder gap is right at the outer edge at 0.008", Accuracy is good as is lockup etc.
Upon inspection, the extractor star is about .003" below the end of the cylinder.
Question, are there shims available to go between the extractor star and cylinder or are extractors available in different thicknesses?
Or am I just SOL?

Roger

 

[unclenunzie]

You probably know this but extractors are fit to the specific cylinder and frame/hand, etc, to create proper carry up timing (and headspace). If you look real close you'll see that there is a bearing surface in the star (around the center pin) which is just a tiny bit higher than the rachets. That's where it contacts and bears on the recoil shield. I'm no expert but I would not recommend trying to shim the extractor. If you have end shake there are bearings which go inside the cylinder and will reduce it, but also widen the cylinder/barrel gap. If you want to reduce the gap and correct end shake, it is likely the yoke barrel needs stretching by the factory or a real revolver smith.

 

[4v50 Gary]

S&W specificies a certain gap between the forcing cone and face of the cylinder as well as between the rear of the cylinder and the frame. Have you checked the latter and if it is w/in specs, leave it alone.

 

[BBBBill]

If you have lots of endshake, then bearing washers inside the cylinder to eliminate all but about .001". You must check headspace when you do that. Off the top of my head it is .060-.066" as measured between the case head and the breech face. You are then left to deal with with the cylinder to barrel gap. Your stated .008" is excessive by the spec, but I've handled many S&Ws that had that much and functioned well enough. Correction for that will entail pulling the barrel, trimming the torque shoulder a specific amount, reinstalling the barrel, trimming the rear face to clear the cylinder face by the desired amount, and recutting the forcing cone. The latter steps are done with a special set of cutters that are guided through the bore and bear on the rear face of the barrel. Not inexpensive work if you are paying a smith to do it.
A skilled amateur can do it with rented tools and access to a lathe to get the torque shoulder relieved. You will need an S&W revolver action wrench (no hammer handles or sticks shoved through the frame window if you want the gun to survive) and the barel facing and forcing cone cutting kit. Brownells used to sell that, but I think the only place to get them now is rental from 4D Reamer Rentals. Mine are NOT for rent. One too many damaged/broken tools cured me of that.
No point in doing any of that if you don't also check the yoke/crane for proper alignment while you're at it. I have occasionally found cylinders that had runout on the face, causing variable cylinder to barrel gap. Truing the cylinder in a lathe is the cure. But only if you are as OCD as I am.