I just picked up a cherry 1967 36-1 and am experiencing a bit of drag on 1 chamber. This one chamber seems to lack headspace; that is, it drags carrying up to firing position and leaving firing position. I identified a slight burr on the firing pin bushing, and tried deburring it by using a small diamond-coated ball-end Dremel tool bit to lightly deburr by hand.

Now it drags much less, but I am concerned about it being on this one chamber only.

Even after deburring, this one chamber still drags enough to lightly scratch the case head, but it's much less noticeable than it was at first.

Does anyone have a theory as to what's going on?

Without actually seeing the revolver, my guess is that the cylinder is not rotating symmetrically for some reason. The extractor rod could be at fault, or the yoke could be slightly bent. If you have a caliper, measure the space between the recoil shield and the back of the cylinder on all five charge hole alignments and see by how much the vary. When you rotate the cylinder outside of the frame, note how much it might "wobble" or be out of round. If you can not figure it out and repair it yourself, a trip back to the Factory might be in order.

Chief38

I'd do the first two first, then after the first two are known to be set properly, the third will fix it. Trimming the forcing cone is the last resort.

If you have end shake, correcting the end shake will correct the forcing cone drag.

Does the cylinder close easily and snap closed. If it doesn't snap closed easily, I'd have the yoke checked. They have special alignment gauges to set it.

It is not uncommon to set the air gap with a file. The preferred way is to use a special cutter. You want the air gap between .003-.010 inch. The air gap must be done square. If you can't cut it square let a shop set it for you.

__________________
NRA Benefactor Member

It's dragging at the breechface end, not the B/C gap. And there's almost no endshake.

I've got a yoke alignment rod for K/L/N frames, but haven't seen one available for J frames... Anyone know where I can get one?

The cylinder does not appear to wobble discernably, but the ejector rod might have a bit of wiggle in it.

Thanks for the input, guys.

You can check the head space with a feeler gauge. The specs are in the faq above.
If the head space is way under limit, the only way to fix it is to have S&W fit a new ejector in it. The center portion of the ejector is what controls the head space on revolver cartridges.

If the rubbing is one of the lugs, take a file and clear it. Do not file the center part of the ejector.

If you have a burr on the firing pin bushing just take a small stone and dress it away. Sometimes the firing pin will cause this if there is some dry firing on the gun.

Edited to say Brownells has the tool

http://www.brownells.com/.aspx/pid=6...ALIGNMENT_TOOL

__________________
NRA Benefactor Member

So they do!

Thanks for the info, 5MN. Gave me an excuse to blow 150 bucks at Brownells.

I have shot it some more and the problem is definitely decreasing. Maybe just needed to be broke in... When I said cherry, I meant it had maybe a cylinder through it before being put back in the box.

But still I will check alignment and headspace... I suspect it's on the tight side.