old British percussion lock sear

[490roundball]

A while back I posted on the antique collectors forum about an antique store find - a cased British 14 bore percussion side by side. 

I think this question might be better aimed at the builders here.

as for the old piece -

the good news - it has cleaned up very well,  most of the case color remained under the very light oxidation. The pictures below show the comparison between cleaned locks and the 150 years of  crud.  Formsby's refinishing formula lifted the old blackened varnish on the stock without the need for sanding or damage to the checkering.  The bores are great,  having measured bore size, wall thinkness and running a scope down to visually inspect them I find they are true to size, no pitting of concern and plenty of wall.  I am now in the process of rebrowning them with a solution from a British gun restorer, pitures of that will follow






now the one problem - at some point in history, the sear of the left lock was replaced with a misfit.  if you look at the sear in the cleaned lock you will notice it is shorter, thinner and has a slight curve to it. the result is that although the lock functions off the gun, it won't work correctly installed.  to get the hammer to the same resting position as the good lock, the left lock has to be at half cock. To match the right's half cock position the left goes to full cock, certainly not a safe carrying situation.

So I need to replace the sear.  I will check around for a better fitting old part, but I think the two most feasable solutions are to have a new replacement made (cast?)or if all else fails, fill the holes and replace the enternals with the parts from a modern set, but that would mean reinletting into the old wood and losing a lot of history.

Any idea of a source for making a reversed copy? Sand cast maybe?   or a good source of old parts?

thanks

[Bill Brockway]

Rick  -

Glad to see that you are retreiving another old double.  I love 'em.

The easiest way to replace the sear is to make another one.  You can find instructions for this kind of work in Chapters 10, 11 & 12 of my book, "Recreating the Double Barrel Muzzle-Loading Shotgun  (Shumway, 1985).

I would use the right hand sear as a pattern.  Just do everything the reverse.    Also, check to be sure the sear noses haven't been shortened.  This sometimes is the case when the sear arm has been bent, as in your gun.  The sear used for the left lock may be a replacement, too, which accounts for it's lack of fit in several places.  It is almost impossible to find a sear to fit a gun such as yours without alteration.  Military guns, sometimes, but sporting guns, almost never.  It is possible, however, to make a new one.

Good luck with your project.

Bill

[Dphariss]

Looks like the tumber, bridal, sear are different on the 2 locks.

Casting is not the answer. Could file a part from bar stock faster and have a better part.
Dan

[490roundball]

Looks like the tumber, bridal, sear are different on the 2 locks.

Dan

Dan
that might be due to the dirt on the one, the other parts are marked to the lock with the same roman numerals, (as is the stock) and match from one to the other.  You can see the number on the lock bolt and mid way along the bottom of the main spring on the cleaned plate.

The unmarked sear is shaped different and is finished off much rougher than the rest of the parts.

And Bill
Thanks for the advice - Yours is a book I have been meaning to get anyway.  I like having a bit of history in the field, I am looking forward to the first bird over a point with this one.

[D. Taylor Sapergia]

I think Dan may be on to something.  It appears to me that the tumbler on the clear lock does not come down toward the bottom of the plate as far as the other lock.  It may have been altered to match the replacement sear, and therefore, may need to also be replaced.

[keweenaw]

It's actually not a huge or hard job to make a new sear from bar stock.  Just saw it to approximate shape and file to finish.  The key is to get the nose to exactly the correct length so that when both hammers are cocked they are exactly the same position.  I would make it from mild steel and case harden it but you could use 4140 and through harden without any difficulty.  It would take me less time to make the new one from scratch than to find some casting somewhere that I would have to modify anyway.

Tom