So apparantly the pins were never tapered... I’ll accept that.
I wonder if the pin hole on one side of the frame is slightly larger than the pin hole on the opposite side....





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I wouldn''t think so, because the pin would then be somewhat looser fitting than the other side, and , at least in theory, the sear, on that side would not square up with the interfacing surface of the hammer.
Someone mentioned deforming the pin slightly, making it slightly out-of-round.
That may sound somewhat like a "shade tree" fix, but I think, properly done, might be ok. As John mentioned, most 'pinned' British boxlocks used a tapered pin, and, while I'm comfortable in saying I do not believe Parker ever employed this technique, it would have been preferable to the way it was done.
Generally, I think the sear spring exerts sufficient pressure to keep the pin centered, but, Russ's gun might suggest otherwise.
I've never liked the idea of using thread locking glues on good guns.

The pin is exceptionally hard and would be extremely difficult to deform it if that route were chosen. I did it once on a pin that shifted a bit with probably every shot. It wasn’t easy to do it.

Go ahead - call me a shade tree gunsmith....





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This is what I have as best I see it.

Upper drawing is normal condition with a Parker (when I look at other guns). Domed pin heads on both left and right are in place, snug with receiver sides; not absolutely flush (they are domed, and not flat-headed); but, possibly are slightly countersunk into a tapered opening, or drill hole in the receiver's side.

Thus, it does not look like either side can draw through it's opening.


I depict one pin all the way through, but do not know how it actually is (or should be). Just using my imagination here, no X-ray vision.


Lower drawing shows the pin head extending from the right side, which is what I have with the gun right now. When I do tap it in, the left side pin head is the one that extends out and the right side then becomes nicely seated. As said, it "reciprocates".

I get the impression you have a replacement pin if, in fact, it has a 'mushroom shape' head on either end. The original pin is nothing more than a straight shaft with no heads but slightly domed on either end..





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I mistakenly believed the dome was on a pin HEAD, but, as Dean indicated the domes are not on a head, but are merely a rounded shape at the END of a single through-pin. So, my drawing with an assumed mushroom shape was way off.

This may in fact be a replacement pin that was just cut a little too long, and is too thin; so that when loose, it just shifts as it is now doing from side-to-side when tapped in from either side. And, since it is one long pin, it never approximates the correct seated siting on both sides at the same time.

My father’s very original-condition 16-gauge VH I assume is correct and has both of the pin domes almost, but not quite, flush with the frame sides. There is a slight convexity you can see and feel.

If the pin on this restored gun does not get any worse during the next month I will try to get through the hunting season with it, then take it to a qualified smith.

A world, not in drop of water, but in a Parker pin.

Thanks to all who have responded.

Most pins I have seen as Dean suggested were rounded on the ends and may jut out slightly to either side of receiver. I also thought pressure from sear spring would keep it in place. It sounds to me like they put a wrong sized sear pin in there that is to long.

Oops typed this, and then went did something else then came back and hit post. Seems you came to same conclusion. Yep I did not think it possible that pin could work the way you drew it without making it a semi-permanent feature of the gun.

BTW I am neophyte as a gunsmitty. I would almost think you could get the right pin and tap into place as it pushes the wrong one out, but then again this where things go wrong. Also don't think I would trust that pin. I would always worry it could fall out then you would be in pickle with sears flopping around.

The sear pin for an 1 or 1-1/2 frame is about .100" longer than the one used in an 0 frame. They are all the same diameter.

Give Lawrence DelGrego a call. He has all manner of Parker parts.

1 and 1-1/2 frame would be different lengths from each other. 1-1/2 and 2 frame are the same length. Since the frames are the same width at the stock head.
The pin lengths correspond with the different widths of the frames.