Lock repair

[Molly]

The photo below is of a lock from "an old rifle".  Two things to observe.  First the lock plate, from the outside, looks really good.  The hammer shows evidence of a lot of corrosion.  The inside view of the lock plate does not show so good at all, esp the bolster.  We removed the spring yesterday after shooting it and there is a significant degree of corrosion that can be seen with the spring removed.  Two questions.  How can one account for the exterior looking so good with the hammer and interior showing a high degree of corrosion?

Second question.  The end of the spring which connects to the stirrup shows more wear than I would like to have on it in order to shoot it. I fear it could easily break.  Specifically the two small "hooks" which go over the stirrup and more specifically the one on the inside.  Is there anyone who can duplicate this spring as I think we would like to replace it now. 

BTW, this lock is from the greatly discussed "Soddy-Daisy" style rifle.

MAS
 

[T*O*F]

How can one account for the exterior looking so good with the hammer and interior showing a high degree of corrosion?

The bottom of the bolster looks to be so thin that it would allow primer and fouling residue to enter into the back of the lock.  Likewise, the lock was probably seldom, if ever, removed for cleaning.

[Gaeckle]

Here's a thought, just an opinion. There was pitting on the exterior of the plate, you can see it faintly around the drum mortise. If you look carefully on the lock tail there appears to be a vertical line, an old engraved line perhaps? If this is the case, would there have been other lines engraved on the plate, both the top and  bottom of the plate? An outline as was done?

I think the plate was polished at one point in time and rebrowned to enhance it's appearance. The interior of the plate was left alone because it can't be seen. That's just my opinion. The pitting probably came from a combination of corrosion of the primers, ambient moisture/humidity and time

[smylee grouch]

I think the guys at Cabin Creek could fix it.

[Bob Roller]

Typical lock found on many American guns.Very simple mechanism.Probably cast iron hammer and plate and as was mentioned.age and neglect plus corrosive caps were no help either.That plate shape is one of my favorites and an easy one to inlet and I made a number of them for Log Cabin in the past.
Bob Roller
 

[Molly]

Interesting and informative observations.  The possibility that the plate was polished has some merit as there are what one might conclude were remnants of engraving.  I never considered that. 

Mr. Roller:  From what period would you think this lock was made.  The rifle was said to be from the 2nd quarter of the 18th century...1826 to 1850.  Might that be a reasonable conclusion based on the characteristics of the lock?

Molly

[Joe Stein]

It looks like the screw holes on the outside are dished inward like happens when a buffing wheel is used.

[Molly]

I now notice marks at the rear of the hammer which look like they also could have been made by a rotating disk.  Some of the critics of this rifle pointed to the lock plate surface as evidence that it was not old.  Additionally some questioned the absence of engraving as a sign it was not old. Seems clear to me that the lock is one that has an age which approximates the age disclosed by the auction house.

[Bob Roller]

Interesting and informative observations.  The possibility that the plate was polished has some merit as there are what one might conclude were remnants of engraving.  I never considered that. 

Mr. Roller:  From what period would you think this lock was made.  The rifle was said to be from the 2nd quarter of the 18th century...1826 to 1850.  Might that be a reasonable conclusion based on the characteristics of the lock?

Molly

Molly,
I am no expert on time frames but I would say 1850 on forward.The muzzleloader never did fade away altogether but was dormant for a long time until revival of interest in the mid 1930's.
Bob Roller

[Molly]

I think you are more of an expert than I!  My guess is about the same as yours.  1850 forward and given other considerations I'll say probably not after 1885/1890.

[D. Taylor Sapergia]

I do not see the claw on the end of the mainspring as being a weak point.  The spring presses downward but also back toward the tumbler and engages the stirrup nicely.  I don't think you need a new spring, Molly.

[Bob Roller]

I do not see the claw on the end of the mainspring as being a weak point.  The spring presses downward but also back toward the tumbler and engages the stirrup nicely.  I don't think you need a new spring, Molly.

Molly,
Taylor is right about that mainspring.In spite of the simplicity that is a good lock and whoever made it knew what they were doing.
I have no idea how many springs like this I have made but the link and claw work fine and the very highest quality locks used them.
Bob Roller

[Molly]

Well, I'm happy to hear these observations however the "claw" (I did not know what it was called) that is on the inside vs outside (the one you see in the photo), is in pretty sorry condition.  I feel it will be OK and the lock functional as long as it does not get much use but if we take to shooting it regularly then ??
My hubby says it really feels good when held in a shooting position.  Very well balanced and very light for a 45 (+/-) cal straight barrel.  If conditions permit we may try to shoot it this week and if so will take the spring out, photo and post it.

[Daryl]

Sounds good. There is a postal match that needs more competitors, you know.