Chambers late ketland plate and internals comparison to percussion locks

[HighUintas]

Can anyone tell me what the closest percussion lock plate and internals or sear bar location is to the Chambers late ketland lock? I'm thinking of a percussion lock and extra barrel.

Or, just converting it to percussion if there's a cap lock plate just a little bit larger so it wouldn't throw off the lock panels look, etc

Not sure I'll pursue this, but considering it.

[Bob Roller]

If the plate profile is the same on the caplock and the flint I would think the mechanisms would be identical.They both use the old style tumbler and mainspring with no link.
Bob Roller

[smylee grouch]

I don't know if Chambers makes a percussion version of that lock, but if you had Another late Ketland flintlock you might be able to convert the 2nd one to percussion for the 2nd barrel. 

[HighUintas]

I forgot to add, that my late ketland lock plate is modified. Rounded the rear finial.

[HighUintas]

I don't know if Chambers makes a percussion version of that lock, but if you had Another late Ketland flintlock you might be able to convert the 2nd one to percussion for the 2nd barrel. 

They don't and there's only one instance of the lock being converted on ALR and it was done by Jim Chambers for David Rase. It seems finding a suitable hammer might be an issue, otherwise I'd go that route.

[parve]

Here's a Chambers Late Ketland with a Chambers mountain Siler hammer:



If it was me I would probably try it this way, especially since you can locate the powder drum wherever you want in relation to the lock plate. Just so long as you don't run too far into the breech plug.

[HighUintas]

Here's a Chambers Late Ketland with a Chambers mountain Siler hammer:



If it was me I would probably try it this way, especially since you can locate the powder drum wherever you want in relation to the lock plate. Just so long as you don't run too far into the breech plug.

That's awesome. Thank you for the help!

I will call Chambers tomorrow to see if they have any more helpful information.

I'm wondering though, is there anything that keeps the hammer from going all the way forward without a drum and nipple in place since the percussion hammers don't come to rest on the lock plate bolster? Those don't have a lip that hits the bolster like a flintlock hammer, right?

I'm not seeing any contact between the bridle and the tumbler on my late ketland when the flint cock is all the way down, so that would need to be addressed if changing to a hammer with no tumbler stopping shelf.

[HighUintas]

I am thinking maybe just solder on a piece of steel on the back of the bridle for the tumbler to stop on but leave a little gap when the hammer is down on the nipple so that it can adequately crush the primer and the bridle doesn't take as much force from the hammer. It would primarily serve to keep the mainspring from coming off the tumbler without a nipple in the drum.

Mine is extremely close to the edge already. I may need to solder a piece on to the flint cock shelf before it gets any closer.

[whetrock]

You have the right idea, but you will have to evaluate and figure out exactly what, if anything, needs to be adjusted.
There should already be a failsafe "stop" built in. The tumbler is usually designed so that, if the cock or tumbler shaft were to break, allowing the tumbler to swing around further than normal, then the back of the tumbler will hit the bridle and stop it from spinning. That's to keep the tumbler from swinging too far forward and allowing the mainspring to slip off the toe of the cam. If it slips off it can punch a hole through the bottom of the mortise.
So you may just need to check to see if the stop does or doesn't need to be built up a little.
On some locks this gap is a little too much, and needs to be built up. You check it by taking the cock off and carefully examining how far the tumbler will swing in relation to the mainspring on the toe. So long as the mainspring won't slip off, it's good.
There's one old reference book that many of us have used that suggests that the shoulder of the cock and this stop should hit at the same time. But that's not exactly right. You want to shoulder to hit first. And you only want the stop on the bridle to hit as a failsafe. So it's appropriate for there to be a gap as you see here when the lock in the rest position. You just need to check to be sure that it will indeed serve as a failsafe, as it's supposed to.
On some locks the shoulder on the cock will slowly wear the top of the plate a little. If the timing is too tight here, such that it doesn't leave a gap where the red arrow is pointing, then when that wear occurs in the plate, the tumbler and bridle will become the main thing stopping the forward travel of the cock. You don't want that. The bridle and tumbler are more fragile than the cock. So, the shoulder should be stopping the cock, and the failsafe should just be a failsafe.








I realize that you already know this, HighUintas, but just to round out the explanation, let me also say that when looking things over, check both the lower leaf arm and also the hook. You don't want the arm hanging over the edge of the plate with the cock in rest position. If it does, then it will punch the side of the mortise when you trip the sear. And of course you don't want the hook to slip off.






I apologize for editing this post several times. Just little hard to explain, I guess. I hope it's more or less clear now.

[Bob Roller]

The Chambers Late Ketland was a favorite of mine and I bought the external parts for them with frizzen hardened and installed including the spring and made a linked mechanism with 3 screw bridle.If I were going to restart lock making the Chambers Late Ketland would be my choice to use for a custom mechanism.I have no idea about how many L&R small Mantons I sent to Germany for pistols.Helmut Mohr told me but I can't remember the number.No problems with these parts reported after years of use.Going to comparison of lock mechanisms I have a strong preference for the top of the line styles seen in cap locks and they were seen in late flintlocks with the linked tumbler with a
 strong  but limber mainspring that produced an abrupt strike of flint on steel.Using the bridle as a brake will guarantee a broken screw or a badly bent one.Maybe a dedicated screw head incorporated in the design of the lock would be a help but failures of these lock made now is rare unless someone releases the hammer of a cap lock and ruins the bridle.
Bob Roller

[HighUintas]

You have the right idea, but you will have to evaluate and figure out exactly what, if anything, needs to be adjusted.
There should already be a failsafe "stop" built in. The tumbler is usually designed so that, if the cock or tumbler shaft were to break, allowing the tumbler to swing around further than normal, then the back of the tumbler will hit the bridle and stop it from spinning. That's to keep the tumbler from swinging too far forward and allowing the mainspring to slip off the toe of the cam. If it slips off it can punch a hole through the bottom of the mortise.
So you may just need to check to see if the stop does or doesn't need to be built up a little.
On some locks this gap is a little too much, and needs to be built up. You check it by taking the cock off and carefully examining how far the tumbler will swing in relation to the mainspring on the toe. So long as the mainspring won't slip off, it's good.
There's one old reference book that many of us have used that suggests that the shoulder of the cock and this stop should hit at the same time. But that's not exactly right. You want to shoulder to hit first. And you only want the stop on the bridle to hit as a failsafe. So it's appropriate for there to be a gap as you see here when the lock in the rest position. You just need to check to be sure that it will indeed serve as a failsafe, as it's supposed to.
On some locks the shoulder on the cock will slowly wear the top of the plate a little. If the timing is too tight here, such that it doesn't leave a gap where the red arrow is pointing, then when that wear occurs in the plate, the tumbler and bridle will become the main thing stopping the forward travel of the cock. You don't want that. The bridle and tumbler are more fragile than the cock. So, the shoulder should be stopping the cock, and the failsafe should just be a failsafe.








I realize that you already know this, HighUintas, but just to round out the explanation, let me also say that when looking things over, check both the lower leaf arm and also the hook. You don't want the arm hanging over the edge of the plate with the cock in rest position. If it does, then it will punch the side of the mortise when you trip the sear. And of course you don't want the hook to slip off.






I apologize for editing this post several times. Just little hard to explain, I guess. I hope it's more or less clear now.

Your message is clear. Thanks, and that is how I understand it to work. It appears mine has quite a gap between the bridle and tumbler. However, I spoke with, I think Barbie, on the phone just now and she said that the flint cock shelf is the only intended stop for the tumbler, so it doesn't sound like they intended and emergency stop in the bridle at all.

[HighUintas]

The Chambers Late Ketland was a favorite of mine and I bought the external parts for them with frizzen hardened and installed including the spring and made a linked mechanism with 3 screw bridle.If I were going to restart lock making the Chambers Late Ketland would be my choice to use for a custom mechanism.I have no idea about how many L&R small Mantons I sent to Germany for pistols.Helmut Mohr told me but I can't remember the number.No problems with these parts reported after years of use.Going to comparison of lock mechanisms I have a strong preference for the top of the line styles seen in cap locks and they were seen in late flintlocks with the linked tumbler with a
 strong  but limber mainspring that produced an abrupt strike of flint on steel.Using the bridle as a brake will guarantee a broken screw or a badly bent one.Maybe a dedicated screw head incorporated in the design of the lock would be a help but failures of these lock made now is rare unless someone releases the hammer of a cap lock and ruins the bridle.
Bob Roller

Bob you are right, I would not want the tumbler to hit the bridle as a stop either. That would probably screw up the internals quickly. I was thinking that if a percussion hammer with no tumbler stop shelf was put onto the late ketland lock, you may want to have a stop for the tumbler on the back of the bridle so that you can let the hammer down all the way (easily) when there is no nipple on the drum or when the lock is out of the gun.

[Bob Roller]

The bridle is the normal resting place for the tumbler IF the hammer is lowered slowly on any cap lock when it's off the gun.The nipple on a cap lock is also the brake and I have seen more than one that looked like a rivet
Bob Roller

[HighUintas]

I acquired a siler, large and small percussion Hammer and tried them on my lake ketland Lock. I don't think the small siler would work. The large might barely work, and barely due to position of the tumbler toe, when the hammer is is hit the drum nipple.

Doing this conversion highly depends on the specifics of your late kettland lock Aunt where you would be placing the powder drum. I think a larger drum would be necessary, at minimum 7/16 in.

Another thing I found is that the Chambers percussion locks, like the mountain and silver, have tumblers that are different from the late kettland. The rear of the tumbler that comes up to the bridle is extended on those, where it would stop the tumbler on the bridle before the mainspring hook slips off the toe when the hammer is at rest. The kettland tumbler has a shorter rear end of the tumbler that does not contact the bridle. So, you would either have to swap out your tumbler or solder a stop onto the bridle or the back of the tumbler. You could also braze, solder, and or pin a shelf on the hammer to stop on the top of the lock plate.

Through email with Jim Chambers, he noted that he thought those ideas would work, but the kettland spring may still be a little too strong.

Taking all of that into consideration, yes, it is possible to do, but would take careful planning and modifications. More than I want to pursue at the moment. I'd rather just build an entirely new gun

[Bob Roller]

I am thinking maybe just solder on a piece of steel on the back of the bridle for the tumbler to stop on but leave a little gap when the hammer is down on the nipple so that it can adequately crush the primer and the bridle doesn't take as much force from the hammer. It would primarily serve to keep the mainspring from coming off the tumbler without a nipple in the drum.

Mine is extremely close to the edge already. I may need to solder a piece on to the flint cock shelf before it gets any closer.

[Bob Roller]

That spring is exactly where it should be with the lock uncocked and frizzen open.I made a lot of these springs before 1967 but after that I bought a new vertical mulling machine and made and years later I made tumblers with a slotted arm for a link and Manton type  mechanisms.Much smoother and it may have been faster.I took time to make sure the main spring was preloaded and when the link is straight down the spring should be at least 1/2 of an inch below.Close tolerances on the two short shafts of the tumbler also enhance performance of any lock and it;s not hard to do this simple job.Tempering these springs to the degree that they are not likely to break or distort is an acquired skill and I leaned it by watching gunsmith George Killen and years later made sure he had 1075 from my shop to use
on his repair jobs.Quality materials are a MUST have and readily obtainable from a number of steel suppliers.I have established what worked for me and my locks and triggers are all over the parts of the world where black powder shooting is practiced and no reported trouble.
Bob Roller