Hi...How did Smith and Wesson accomplish barrel pinning? Was the drilling done after the barrel was joined to the frame? Was the frame drilled prior to joining the barrel? BT

The rough finished barrel was installed into the frame, the headspace and BC gap set, etc., then the hole was drilled through the frame and across the top of the barrel threads/shank, the barrel removed for final finishing, then re-installed and the pin installed.

Unfortunately this is not correct, although logically this sounds like it should be.

Invariably, when a never-installed barrel intended as a spare part is found, you will find the pin groove already cut. Depending on period this can be either a half-round groove which is a little wider than the pin diameter, or a flat-bottomed rectangular groove milled straight across the barrel shank.

Both the groove in the barrel, and the hole in the frame, were machined in a jig to properly locate them.

I've taken the barrel off of a few pinned revolvers, and the pin in each case was not very tight. I'm pretty sure that the barrel could have been rotated a degree or two with the pin in place.

Was the pin intended to prevent loosening, or just to limit it?

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Mark

It was meant to extremely limit it.

In my earlier post, I didn't mean to imply that the groove in the barrel shank was formed from the drilling of the frame, since it is a few thousandths larger than the actual pin, and it would most likely snap a drill bit off when it hit the threaded area if done while cross drilling the frame. The groove is milled into the shank ahead of time.

The other poster may not agree with my post, but there was a thread running here several months ago ( I can't find it in search mode, but then again I never can seem to find anything in search mode, which is probably due more to my poor computer skills than any short coming of the forum software) with posts by some very fine gunsmiths describing the process exactly as I did here. If they and I are wrong, then I will happily stand corrected ( and enlightened), but I will need to see some proof to the contrary first.

Well, nothing like conflicting stories to settle the matter. And I thought I'd learn something here! BT