Experiments with a properly tuned flintlock

[dave_person]

Hi,
I want to show these photos that demonstrate what I consider good performance in a flintlock. The lock is a Chamber round-faced English lock (which I consider the best lock commercially made today). However, it was tuned by me, springs balanced (frizzen spring opens at 30% of the force required to pull flintcock to full), and the frizzen was case hardened. The first photo shows sparks from a fresh sharp flint:

Now I turn that flint around so the dull blunt end faces the frizzen:

and fire:

Then I coat the frizzen and flint with inletting black to simulate heavy thick greasy fouling on a humid day and fire:

Then I picked up a small piece of quartz from my driveway:

and fired:

In all cases, the lock would have ignited the powder in the pan and fired. This is what I look for in a lock. I have now fired more than 600 rounds from this rifle without a single misfire or hang fire even when it was dirty and the flint worn to a nub. I've gone through only 10 flints during that time and I replace them when they have no discernible edge not when the lock fails.
dave

 

[Brokennock]

Excellent post, thank you very much. I really do appreciate it. Can you give us any more detail on how you achieve these balanced springs? How do you measure/weigh the force required to pull the flintcock to full, and the strength of the frozen spring, to arrive at the 30%?

Greatly appreciated, thank you,
Dave

 

[Eterry]

Thats a great post, if a picture is worth a 1000 words...there's plenty to talk about there. I'd like to have a tuned lock, but probably cant afford it, so I'm gonna practice on mine.

I noticed the pan doesn't always open completely on my Chambers Lg Siler, but its not the lock's fault. Was playing with it and noticed the frizzen "arm" is rubbing the lock mortise. It wasnt, but it is now. The screws are timed so i guess the stock has swollen...its rained 15 Saturdays since January 1 here.

So I took it apart and noticed the frizzen spring is only being contacted half way by the frizzen "hump". Excuse me if i don't know the vernacular. Someone please set me straight.

Its raining here now...again...and my files are in the shop. I tried dressing it with a whetstone, all i had at hand, but that's REAL slow going. I gave up, and gonna try again in the morning.

My plan is to gently file the frizzen arm so it doesnt contact the wood. The screws were snug, but not overly tight, IMHO.
Next I think i need to address the frizzen spring only being contacted about 50% but the frizzen "hump". I have a set of needle files that should work.

Dave, I know you do this for a living; but would you share a tip or two to help me with this lock.
The last time I shot it, the frizzen wasn't always opening all the way. I chalked it up to being dirty...but its clean now, and I see a rub mark on the mortise.

 

[PluggedNickel]

Awesome post per usual Dave!

 

[dave_person]

Excellent post, thank you very much. I really do appreciate it. Can you give us any more detail on how you achieve these balanced springs? How do you measure/weigh the force required to pull the flintcock to full, and the strength of the frozen spring, to arrive at the 30%?

Greatly appreciated, thank you,
Dave

Hi,
I use a small spring scale for the flint cock and usually a trigger pull scale for the frizzen unless the force required to open it is more than 10lbs. In that case, I use the small spring scale. Keep in mind, that I am not so much concerned with absolute values of force but the ratio between the flint cock and the frizzen. So when I balance springs, I first set up the main spring to be strong and then adjust the frizzen spring to be about 30% of the force. Adjustment can mean heating and bending the spring, then hardening and tempering, or just grinding the spring. It can also involve grinding and reshaping the toe of the frizzen. On some locks it may require all of those things.

dave

dave

 

[dave_person]

Hi Eterry,
I have a little trouble understanding what you are describing. If the pivoting arm of the frizzen is rubbing against the stock on a Siler lock it suggests to me that the builder incorrectly inlet the lock too deep. The lock should go in no deeper than the lower edge of the bevel. The bevel should be above the surface of the wood. That would prevent the frizzen from rubbing. I would be very careful about thinning the pivot arm because you may create a sloppy fit of the frizzen between the lock plate and pan bridle. You don't want to thin the part where the frizzen screw goes through. Frizzens that don't open completely are a common problem on Siler locks. However, you first have to determine if the frizzen is actually not opening completely or is it actually bouncing back after opening. You cannot tell that by watching the lock fire. Close the frizzen, put a small piece of tape on the frizzen spring where the curl on the frizzen pivot arm hits it, and fire the lock. Look to see if the tape is dimpled. If it is, the frizzen opened and bounced back, if not, the frizzen did not open all the way. If there is bounce back, the frizzen spring needs to be strengthened by heating it and opening the bend and then hardening and tempering it. If the frizzen actually did not open, then the spring may need to be weakened or the toe of the frizzen reshaped so the frizzen kicks over faster as in this example:
https://www.muzzleloadingforum.com/threads/building-a-chambers-little-fellas-rifle.110688/page-3
Scroll down until you get to the lock part.

dave

 

[Eterry]

Thank you very much Dave.

I know the toe (now i know what to call it), is not making complete contact with the spring. I assume this is not correct. Looking at the toe you can see it isn't flat where or makes contact, one half is slightly higher than the other.

I'm thinking dressing it until it makes contact across the width of the spring is needed.

As to the inletting... that's on me. But i learned under close inspection the side of the curl of the frizzen is very rough, and is making contact with the wood.

I'm omw to the thread you provided...
Again, thanks greatly for your time and help.

 

[Eterry]

Ok, the curl wasn't as rough as i thought... the problem is too much wood. That's a topic for another thread.
Been tweaking the lock... I'll know more soon.

 

[Howie1968]

Thats a great post, if a picture is worth a 1000 words...there's plenty to talk about there. I'd like to have a tuned lock, but probably cant afford it, so I'm gonna practice on mine.

I noticed the pan doesn't always open completely on my Chambers Lg Siler, but its not the lock's fault. Was playing with it and noticed the frizzen "arm" is rubbing the lock mortise. It wasnt, but it is now. The screws are timed so i guess the stock has swollen...its rained 15 Saturdays since January 1 here.

So I took it apart and noticed the frizzen spring is only being contacted half way by the frizzen "hump". Excuse me if i don't know the vernacular. Someone please set me straight.

Its raining here now...again...and my files are in the shop. I tried dressing it with a whetstone, all i had at hand, but that's REAL slow going. I gave up, and gonna try again in the morning.

My plan is to gently file the frizzen arm so it doesnt contact the wood. The screws were snug, but not overly tight, IMHO.
Next I think i need to address the frizzen spring only being contacted about 50% but the frizzen "hump". I have a set of needle files that should work.

Dave, I know you do this for a living; but would you share a tip or two to help me with this lock.
The last time I shot it, the frizzen wasn't always opening all the way. I chalked it up to being dirty...but its clean now, and I see a rub mark on the mortise.

you've got that right about the rain. here in east texas its only been dry a handful of days

 

[Brokennock]

Hi,
I use a small spring scale for the flint cock and usually a trigger pull scale for the frizzen unless the force required to open it is more than 10lbs. In that case, I use the small spring scale. Keep in mind, that I am not so much concerned with absolute values of force but the ratio between the flint cock and the frizzen. So when I balance springs, I first set up the main spring to be strong and then adjust the frizzen spring to be about 30% of the force. Adjustment can mean heating and bending the spring, then hardening and tempering, or just grinding the spring. It can also involve grinding and reshaping the toe of the frizzen. On some locks it may require all of those things.

dave

dave

Thank you good sir.

 

[Col. Batguano]

For those of us lacking a forge, could you use a campfire, tin can, and a bunch of charcoal (from the wood nit the briquettes) or maybe a charcoal fire in your Weber kettle? Obviously the temperature control would be tricky, and lacking a thermometer you could only do it by color.

 

[zimmerstutzen]

A proper steel frizzen needs to be hardened and then tempered. There is no advantage to case hardening a proper steel frizzen other than to add some additional carbon to the surface layer.

 

[dave_person]

Hi,

A proper steel frizzen needs to be hardened and then tempered. There is no advantage to case hardening a proper steel frizzen other than to add some additional carbon to the surface layer.

Which is exactly why case hardening has an advantage and why I do it on every frizzen.

dave

 

[dave_person]

For those of us lacking a forge, could you use a campfire, tin can, and a bunch of charcoal (from the wood nit the briquettes) or maybe a charcoal fire in your Weber kettle? Obviously the temperature control would be tricky, and lacking a thermometer you could only do it by color.

Hi David,
Use charcoal for what? Casehardening, tempering? Unless you are set up for casehardening with a forge or oven, I would not bother with it. All modern frizzens are high carbon steels and can be simply through hardened by heating to red with a torch and quenching and then tempered in a kitchen oven. They will perform very well. My casehardened frizzens work just a bit better.

dave

 

[Col. Batguano]

Dave's frizzens seem to spark to beat the band, and his carbon packing method seems to generate fantastic results. I suspect he's also changed some of the angles with the cock and frizzen face too. I've been thinking about getting a new and improved frizzen from Track for my large siler. Mine (which is the factory one) sparks ok, but not that great, and Dave's demo photos really shows me what is possible. More sparks will generate faster and hotter pan ignition. more consistent and faster lock speed and less barrel dwell time.

I asked about the campfire thing because 90 minutes with a torch is a LOT of gas to go through, but it's only a few logs, or half a bag of briquettes.

I meant the carbon and bone carbon for infusing more carbon in to the frizzen face. Remember a few months ago when I couldn't get it to spark at ALL? That was right after I put the whole thing together after 2 years in the shop on the bench in building it.

I took your advice and took the frizzen face to a large drum sander to get down below that top layer of steel that I had driven the carbon out of during the repeated heatings and then quenchings to soften it up for engraving, and then re-harden for shooting.

 

[JS60]

but it's only a few logs, or half a bag of briquettes.

Please remember that the frizzen must reach critical temperature before quenching for the hardening to take.

(Most times that ends up being a bright cherry red, and it's also when a magnet won't stick to it).

That sort of temperature is usually a lot to ask from logs or charcoal, ... (unless you have a way to force air through it like you would in a forge.)

 

[Pletcher]

With a properly prepared frizzen and proper springs one should be able to get large quantities of sparks. The pan fire will obviously build faster with many rather than few sparks. With proper geometry those sparks should be directed into the pan instead of in front of the pan - which does happen. Pictures are very helpful in determining this.

The lock in the photo below had a cracked frizzen. The lock left the fall shoot with Jim Chambers. He returned it with a new frizzen installed and a few other "adjustments". Needless to say I am very pleased with the spark production.

Regards,
Pletch

 

[LRB]

Please remember that the frizzen must reach critical temperature before quenching for the hardening to take.

(Most times that ends up being a bright cherry red, and it's also when a magnet won't stick to it).

That sort of temperature is usually a lot to ask from logs or charcoal, ... (unless you have a way to force air through it like you would in a forge.)

Critical temperature is not when the steel loses magnetic attraction. Critical temperature varies with different steels, but loss off magnetic attraction is always 1414°F. Critical temp for most common high carbon steels is 1475°F, some alloys like 5160 require a tad more, around 1500°F , so when the steel loses magnetic attraction you need to get it one or two shades of red hotter, then quench. Pretty much when it begins to turn orange, but colors are dependent on the lighting. Dim light to judge high temp colors, good light for temper colors. Quenching at just non-magnetic is not allowing the steel to come to a fully homogenized internal solution. Best results come from a short soak at the critical heat, whenever possible or practical. Just a minute or so for most of the 10XX steels.

 

[FlinterNick]

Why did the Wheellock Mechanism use a small piece of raw Iron pyrite and not a flint ? I was watching a demo online of a one being fired, the shooter stated that flints can’t be used.

 

[LRB]

Why did the Wheellock Mechanism use a small piece of raw Iron pyrite and not a flint ? I was watching a demo online of a one being fired, the shooter stated that flints can’t be used.

Because a wheellock works like a Zippo cigarette lighter. The hardened wheel rakes off tiny pieces of the soft pyrite which oxidize and burn as sparks ignited from the friction. A flint would be too hard and not produce sparks, just be chipped away and ruin the wheel.