A Bad Fly or A Trash Lock?

[PathfinderNC]

This 7 month-old small Siler lock is not engaging at half **** much. It will 'click in' half **** fine several times and then it will roughly skip over the half-**** but engage solidly at full ****. This happens both on and off the gun so I believe it's not a lock mortise issue. Also, I checked the bridle and its not too tight nor loose.
Interestingly, when the lock isn't engaging at half ****, if I give the side plate a good stiff tap, it will thereafter click nicely into half-**** a few more times. (That's why I think it's a bum fly). Same thing when it's off the gun; a good tap on the **** screw head and it will then engage in half-****.
I have it very well lucubrated with clipper oil.
I compared it with another small Siler lock I have and in comparison it looks really crude and obviously unpolished. It's on my Sparrow pistol, so I was wondering if rather than sending it off to be repaired ($$$), maybe I can take the lock apart myself (a first time doing that for me) and just remove the fly. Or, is this lock just trash? (Pics attached)
I'm bummed that I have to do this with a new lock that came from a pretty reputable dealer.
Thanks,
Bob

 

[TDM]

The fly doesn’t look damaged from what I can see in the photos, but it may be a tad short or worn short.

 

[PathfinderNC]

The fly doesn’t look damaged from what I can see in the photos, but it may be a tad short or worn short.

It's just a baby lock, like maybe 7 months old :-(

 

[TDM]

It's just a baby lock, like maybe 7 months old :-(

Ha! I’m certainly no expert, but it does look to me that there is minimal engagement surface on the fly.

 

[Sean E Bug]

does the rifle use a set trigger? if it does not you can just get rid of the fly and see if that fixes your issue. if you do have a set trigger, I would take the lock apart and clean and lubricate. the fly might be getting hung up and not moving properly. also check for metal burs. if the issue persists I would but a replacement fly and try that.

 

[PathfinderNC]

does the rifle use a set trigger? if it does not you can just get rid of the fly and see if that fixes your issue. if you do have a set trigger, I would take the lock apart and clean and lubricate. the fly might be getting hung up and not moving properly. also check for metal burs. if the issue persists I would but a replacement fly and try that.

I noted that it's on a pistol. I am leaning toward your thought about removing the fly all together, if it looks like the rest of the parts are OK.

 

[Phil Coffins]

The fly looks too short, the tip should be a tiny bit higher so the sear will drag it back as you **** the lock. Having a fly in the lock even without a set trigger insures the sear doesn’t catch in half **** when fired. Your tumbler has the fly on the outside so replacing it shouldn’t be difficult. Use a main spring vice though.
6AD4B69C-3E1C-47CE-B512-BEBA21611112 by Oliver Sudden, on Flickr

 

[PathfinderNC]

The fly looks too short, the tip should be a tiny bit higher so the sear will drag it back as you **** the lock. Having a fly in the lock even without a set trigger insures the sear doesn’t catch in half **** when fired. Your tumbler has the fly on the outside so replacing it shouldn’t be difficult. Use a main spring vice though.

Thanks Phil.
But Why would it not work unless I tap the lock though? I was guessing it wasn’t smooth and getting caught. And I wonder if new flies for this lock are sold already hardened?

 

[SDSmlf]

I’m on the deburr, clean and lubricate team. Easy to do. With a stone or wet paper on a flat surface, knock off any burrs and polish all surfaces that rub against each other. Clean everything up and re-assemble, then lubricate the moving parts with the lightest quality oil you have. Not guaranteed, but will likely solve your issue. If not, report back.

 

[Phil Coffins]

Thanks Phil.
But Why would it not work unless I tap the lock though? I was guessing it wasn’t smooth and getting caught. And I wonder if new flies for this lock are sold already hardened?

It maybe just a that close to working that the tap is shaking it over.
Ask the seller and if it isn’t it’s very easy to harden.

 

[sussexmuzllodr]

Hey Bob I would take it all apart and polish everything lube and try.

 

[dave_person]

Hi Bob,
Cycle the lock without the fly to assure that it is the fly that is the problem. It may be that the tip of the fly is too short such that the sear does not catch it pushing it back to uncover the half **** notch when you are bringing the flintcock back to half ****. That it works a few times after tapping the gun may simply mean the fly rotates OK and you are knocking it back on the tumbler when you tap the gun but your sear just doesn't catch it. It looks short to me in the photos. When you **** the lock, you should feel the sear riding over the fly as you go from half to full ****. If you don't feel that very slight bump, it may be another indicator that the fly is too short. You can get replacements that are already hardened and tempered. With the lock out of the gun, you should be able to see what is happening as you **** the lock. There is a good "sticky" thread at the top of the list for this Gunbuilder's Bench forum about taking a lock apart. It might be worth reviewing.

dave

 

[PathfinderNC]

Hi Bob,
Cycle the lock without the fly to assure that it is the fly that is the problem. It may be that the tip of the fly is too short such that the sear does not catch it pushing it back to uncover the half **** notch when you are bringing the flintcock back to half ****. That it works a few times after tapping the gun may simply mean the fly rotates OK and you are knocking it back on the tumbler when you tap the gun but your sear just doesn't catch it. It looks short to me in the photos. When you **** the lock, you should feel the sear riding over the fly as you go from half to full ****. If you don't feel that very slight bump, it may be another indicator that the fly is too short. You can get replacements that are already hardened and tempered. With the lock out of the gun, you should be able to see what is happening as you **** the lock. There is a good "sticky" thread at the top of the list for this Gunbuilder's Bench forum about taking a lock apart. It might be worth reviewing.

dave

Thanks Dave.
I will try and take the lock apart today (a first for me). I am going to look over the thread on disassembling a lock. I hope I don't mess it up.

 

[Eric Krewson]

Chambers locks are guaranteed for life, send it back and let the experts fix it.

 

[PathfinderNC]

Chambers locks are guaranteed for life, send it back and let the experts fix it.

Hi Eric, I dont know if it is a Chambers Siler lock. I got it from MBS.

 

[PathfinderNC]

Got it!
I took the lock apart down to the exposed tumbler and removed the lil' fly. The parts sure don't seem polished in there, and seeing scratch marks on the plate under the sear. Anyway, I reassembled it without the fly, oiled it with clipper oil and it goes into half-**** every time correctly. It doesn't feel as smooth as my other small Siler, but it is OK for now.
I will see if I can find a fly for this guy and get 'er right.
Thanks everyone!

 

[Snooterpup]

The fly doesn’t look damaged from what I can see in the photos, but it may be a tad short or worn short.

I agree with you and Dave Person. The fly looks to be a bit too short with the grind geometry off, not properly kicking the fly out of the way when cocked. Send the rascal back for repair/replacement.

 

[EC121]

It looks like a kit. Those rough parts aren't typical of a lock from Chambers. This is a learning opportunity. Disassemble it and polish all the contacting surfaces. A new fly is already hardened and can be replaced.

 

[sussexmuzllodr]

Bob. Smooth out the fly with crocus cloth and give it a retry. SM

 

[EC121]

I use wet-or-dry sandpaper and polishing sticks plus a stone to reach the various parts.