AmericanLongRifles Forums
General discussion => Gun Building => Topic started by: smart dog on February 11, 2024, 04:33:44 AM
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Hi Folks,
Locks are the topic of many informative but also contentious threads on this forum. I believe, that is a good thing and frank, objective discussion of things good and bad about locks is very valuable. Unfortunately, discussions often go down rabbit holes that lead to nothing but the "Cheshire Cat" and the "Mad Hatter". Here is a good lock.
(https://i.ibb.co/k8WxfXr/finished-musket-6.jpg) (https://ibb.co/zR0rYZL)
It is the pattern 1756 used on British muskets from 1756 onward with little change until the percussion era. It is a big lock, 6 7/8" long and 1 1/4" wide behind the pan. Its large size makes it easy to see and understand the mechanism. It is also a very good lock to learn lock making because being large, the parts are also bigger and thicker, allowing more margin for error. It is also very simple, no fly detent, no stirrup in the tumbler, no "waterproof pan", no roller frizzen, etc. Yet it was highly successful, helped the British dominate much of the globe, and helped us win our independence. Why? Because it worked and worked well. It is also an excellent showcase for good basic lock design. Let's look inside.
(https://i.ibb.co/PrJFtsn/lock-21.jpg) (https://ibb.co/j8qbH92)
(https://i.ibb.co/2MXQfkk/lock-22.jpg) (https://ibb.co/JpX4Mss)
(https://i.ibb.co/Kr0Tk7X/lock-23.jpg) (https://imgbb.com/)
(https://i.ibb.co/0Xttnw0/lock-24.jpg) (https://ibb.co/mB88Rxn)
(https://i.ibb.co/4pWsdQd/lock-25.jpg) (https://ibb.co/GR7sThT)
(https://i.ibb.co/VJfS6MC/lock-26.jpg) (https://ibb.co/FmRwp8Y)
Nothing fancy, just good physics. I built this lock and included a lot of historical details. There is a crown and inspector number and "FG" stamped inside. The "FG" indicate the lock was made by Joseph Farmer and Samuel Galton, both of whom were Quakers. First, note how the mainspring fits well up the foot of the tumbler and the end of the hook tucks right into the instep of the tumbler at full cock. That means it is getting the most mechanical advantage it can by bringing that point of connection on the tumbler as close to the axis of the tumbler as possible. Note the lower leaf of the mainspring is straight when the lock is fully cocked.
Also note the tall tab on the spring for the screw positions the upper leaf of the spring low on the plate. That helps assure a large barrel can be fitted and the spring does not break into the barrel channel. The mainsprings on some modern made commercial locks are poorly designed making it impossible to do that. The fit of the sear to the tumbler is very precise. Look at the fit of the sear spring to the sear. The end of the lower leaf approaches the sear lever at a fairly low angle and the end of the leaf tucks against the back edge of the boss on the sear. This provides great potential for adjusting trigger pull only limited by the fact that the tumbler does not have a fly detent. Consequently, you cannot make a trigger pull much less than 3 lbs. Of course that was no issue for a musket but it would be if you try and turn a Brown Bess into a target shooter. The bar of the sear is located close to the lower edge of the lock plate but it does not change position when at rest, half, or full cock. As a result it is easy to fit a simple trigger such that it doesn't rattle badly at any position of the flint cock. With respect to precision fitting, it is very nice to have extremely close tolerances but not necessary. Flintlocks are not jet engines with blades spinning under high heat at thousands of rpms for hours. The tumbler rotates about 120 degrees max and even over its entire working life, it won't be cycled anything like the fan in your window. Precision machining is nice but not necessary. The greatest flintlocks ever made were made by hand. Even this horrendous India-made Brown Bess lock was made to work reliably without machining.
(https://i.ibb.co/JskRDN9/India-made-brown-bess-tumbler-and-lockplate.jpg) (https://ibb.co/fx0Yjbs)
However, I am NOT excusing poor work, advocating neglecting the skills to produce precise fitting, or questioning the technical superiority of good machine work. Good machining enables high quality work to be done at much lower cost and be repeatable at industrial quantities. Even Paul Bunyan and Blue Babe couldn't keep up with the chain saw. But it is ironic, that I've salvaged many commercially produced locks from poor manufacturing, design, and machine work only using tools held in my impaired hands.
Let's look outside. The pan cover to pan fit is very good, something not hard to do with good assembly technique. Fit the frizzen to the pan, then clamp it in place, drill the thread sized hole through the bridle, frizzen and lock bolster. A drill press is pretty important for that. Then place a very fine shim (1/64" or so) under the back edge of the pan which lifts the frizzen up a tiny bit and drill the clearance hole through the bridle and frizzen. If you don't do that, you may find the front of the pan cover lifted off the pan when you insert the frizzen pivot screw. The shim will prevent that and you will usually only need a few swipes of a file across the top of the pan and bottom of the pan cover to bring the two back in close contact. However, don't fuss with that until you install the feather (frizzen) spring. Get that put in place and make sure the top surface of the spring is flat with the toe of the frizzen, even if you have to bend the spring or file the toe to match.
(https://i.ibb.co/vw6BMpk/lock-27.jpg) (https://imgbb.com/)
Doing that will create a nice smooth action of the frizzen on the spring without a side or corner of the toe digging a trench into the spring. There is prevailing rubbish perpetuated online that the feather spring only needs to be strong enough to hold the pan cover shut. The battery (frizzen) must put up enough resistance to the flint to create sparks when everything is covered with greasy fouling and the flint is dull. It does not matter how often you clean your battery and flint while shooting, that basic physics applies. The most common sparking problems I encounter on the shooting line are shooters with weak feather springs and their locks don't spark after 10 rounds. Often the frizzen does not open completely on these locks. Consequently, the owners obsess that their feather springs are still too strong. I take a little piece of masking tape and put it on their feather springs where the curl of the frizzen toe will contact the spring. They fire the lock and are amazed to find a dimple in the tape. The frizzen opened completely but bounced back because the spring was far too weak. Don't kid yourself, you cannot see rebound. Their feather springs need strengthening. In fact, the force required to open the frizzen should be 30-40% of the peak force required to pull the flint cock from rest to full cock. On a Bess lock, I adjust that ratio such that the force for cocking the lock to full is more like a ratio of 25% because the massive flintcock needs a lot of force to get going quickly. Anyway, here is the lock firing. You can see how the micro-second burst of photos shows the great amount of spark directed to the pan, and how they sputter and persist for several moments.
(https://i.ibb.co/FbZ0vbq/lock-firing-1.jpg) (https://ibb.co/0j4FNjV)
(https://i.ibb.co/j82zQxb/lock-firing-2.jpg) (https://ibb.co/8mpbfRN)
(https://i.ibb.co/dttPjnQ/lock-firing-3.jpg) (https://ibb.co/tzzqQyb)
Many flintlock shooters focus on lock speed and sparking but those are not the only critical measures of performance. I recently worked over 2 locks made by the same manufacturer that sparked very well initially and seemed pretty fast but the geometry forced the flint to hit the battery almost straight on and after 3 shots flints were knapped dull. Both locks had no good options for adjusting the length, orientation, and position of the flints because the frizzens were not tall enough and the surfaces curved toward the cock so you could not use a longer flint and close the frizzen at half cock. A shorter flint allowed the top jaw to hit the frizzen before the flint. These locks are just poorly designed. A good flintlock will fire the priming many, many times in a row using the same flint and that criteria is as important as speed and initial sparking. The British expected their pattern 1756 lock used on the Brown Bess to fire the pan 40 times without a misfire using the same flint. The French expected their locks used on the model 1763s (heavy and light 63s) to flash the pan 120 times without a failure and using up no more than 3 flints. Ideally, a good flintlock produces good sparks, is fast, is easy on flints, and flashes the pan on every shot regardless of all but extremely wet conditions.
dave
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Interesting and informative post. Thanks.
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Great write up Smart Dog! I agree that proper geometry creates a superior lock.
Thanks for sharing!
William
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Quite informative. Thank you.
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Thank you!
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Harden the top jaw ;D ;D ;D ;D.
Bob Roller
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What an excellent post!
Thank you Dave for taking the time to put it together. I will likely have to re-read it a least a couple more times in order to fully absorb the info.
Well done indeed.
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Great primer, thanks. Copy, print, and file.
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Dave once again thank you for another informative article.
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Harden the top jaw ;D ;D ;D ;D.
Bob Roller
Hi everyone and thanks,
Bob the plate, flint cock, and top jaw are case hardened and then tempered to blue. What you cannot see is that I cut teeth in the jaws to hold the leather firmly. Those teeth would be worn down quickly if the jaws were not hardened.
dave
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Harden the top jaw ;D ;D ;D ;D.
Bob Roller
Hi everyone and thanks,
Bob the plate, flint cock, and top jaw are case hardened and then tempered to blue. What you cannot see is that I cut teeth in the jaws to hold the leather firmly. Those teeth would be worn down quickly if the jaws were not hardened.
dave
My wisecrack was offered as farce but I have also cut "teeth" on the upper and lower clamping surfaces and on my own lock,checkering on the bottom jaw..The last flintlocks I made were externally L&R Durs Egg in 2019 ad delivered them at the CLA Show in Lexington KY..
Bob Roller
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An English lock should have an English flint. Just saying! ::)
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An English lock should have an English flint. Just saying! ::)
PLUS Curtis&Harvey black powder ;D ;D.
Bob Roller
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An English lock should have an English flint. Just saying! ::)
Hi Daryl,
Unfortunately, British soldiers complained all the time about poor quality English flints except for a limited supply that came from Suffolk. They loved French flints and imported 2.5 million of them between 1730 and 1750. Even as late as 1779, British officers favored captured French flints.
dave
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LOL- tks for the history lesson - I guess French flints are OK then.
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LOL- tks for the history lesson - I guess French flints are OK then.
I have read that the British used spall flints and did not start making the flints we use today until at least the last half of the 18th c. True? I dunno. The French were making “modern” flints much earlier and it is my understanding that the early Besses had a cock lower jaw designed to hold the impact bulge on the spall. I have read that the British were using French flints during the American War for Independence. But ????
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Very informative and excellent craftsmanship.
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Hi Dan,
From what I've read in Bailey, Goldstein, and others, flints were a constant problem for the British. Before the mid 18th century, flints were "spall" shaped, which looked like thick unrefined chips of flint. Later they were wedge shaped with one good edge and a wide back. Near the end of the century they started making double edged platform shapes, which are what we are used to today. Goldstein shows a couple of Bess examples with depressions ground in the top and lower jaws, presumably to better hold fat spall or wedge shaped flints. I am not sure how wide spread that was. I've not seen it on any musket that I've examined on which I could see the faces of the flint jaws. I think the French were making double edged flints early in the 18th century, which was one reason they were preferred but they were 30% more expensive for the British. Erhard Wolf in his book on German jaeger rifles, has an excellent section about how flints were produced in Europe. They were mined from deep shafts in the earth and kept in humid, cool conditions until knapped and after during storage. Flints were usually shipped in barrels with damp rags on top and stored in cool damp places. That prevents them from drying out so they knap more easily and are less likely to chip and crack. In England, much of the flint came from caves close to the surface and in seams exposed to air. As a result, the flints were drier and much more brittle. Eventually, the British sourced flints from deeper mines in England that served well.
dave
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Cool beans! Thanks Dave and Dan.
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Great information Dave. Have you ever thought about writing a book?
Hank
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Thanks.
Often what one finds in literature is “incomplete.” And to be honest Muskets are outside my field of interest.
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Thanks.
Often what one finds in literature is “incomplete.” And to be honest Muskets are outside my field of interest.
Out of mine as well.The ONLY military flintlock gun I like is the 1803 Haroer's Ferry and it is a rifle and good
looking (to me)at least.Eastern high end target and hunting rifles have long been my top muzzle loaders and
there are times I wished I had went to wood working instead of small devices made of steel.
Bob Roller
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That was an excellent tutorial on lock geometry. You obviously put a lot of time putting that together for us. Thank you!
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Thanks for the excellent post!
Gerald
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I've always used French amber flints if I could get them! They are a little stronger when knapped thinner than the English counter parts. At one time Dixie was selling 'uncirculated" French amber musket flints with the rounded back. Still have one in my collection. Hugh Toenjes
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I had read many moons ago, that both sides at Waterloo used the same flints, mined at Brandon.
Lot of water has gone under the bridge since I was down those mines at Grimes Graves..
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Hi Richard,
Brandon is where the best English flints were mined.
dave
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Indeed Dave,
Huge nodules of transparent black flint, the sort that Hawker recommended.
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So, since this is the subject of locks, what do you guys use to (the easiest method) remove the casting and polish up the inside of the flash pan?
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Well.....someone (Jim Kibler) gave a warning about using the L&R lock. I have other L&R's that work fine....and I blame myself as I should have scrutinized the lock much more when I first received it. And I'm not trying to turn this post into an L&R bashing, but hopefully more of a warning to anyone else who purchases this lock to give it a very thorough once (or twice) look over before you invest time in it.
In fact, I had to send it back when I first received it as the bridle was incorrectly drilled. L&R replaced that.
Now, this lock takes a smaller (5/8 length) flint and all I had at the time was 3/4". That still doesn't make up for my failed scrutiny of the lock when I got it back "fixed".
I received my shorter flints yesterday, and didn't get a chance until last night to install one. The lock sparks great......but then I notice the cock doesn't line up with the frizzen. >:( At first i thought i was crazy...then I started to examine the "squareness" of the pan to the lock plate, etc. It was late last night so I set it aside.
So, now I've determined the frizzen attachment hole has been drilled incorrectly. Yeah...you think I would have noticed this when I was filling the lock, removing the "water proof" lug on the pan cover etc. But I didn't.
So, now I will again contact L&R (who did a quick turn around the first time I sent it back) for a replacement pan\frizzen. I thought of drilling out the existing hole, slugging a bushing in it, then drill the hole square, but I got other things to do.
I placed the white line on the picture to emphasize how far off the pan cover\frizzen is from square.
(https://i.imgur.com/xZqqfPbl.jpg)
Here's another pic with the cock lowered to rest on the frizzen
(https://i.imgur.com/YBhce0cl.jpg)
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Which model L&R lock? I see a small roller on the frizzen toe, I think. Durs Egg?
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Which model L&R lock? I see a small roller on the frizzen toe, I think. Durs Egg?
Also L&R Manton has one.
Bob Roller
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It’s the Manton.
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I really like the design of teh L&R “Manton” which its not from what I have read. I beleive that its actually a Stoudenour(sic) but this means it was probably made for them by a “lock filer”. This is a great pistol lock. The design does not jar to pistol hardly at all when it “fires”.
However, in recent year the quality has “slipped” at L&R.
I have not used the “1700” flintlock in sometime. I have 2 of the percussion versions in a drawer for s project I need to get back too, these seem to be OK. I met a guy at the range that had a L&R on the rifle and it was unusable. It was so far “out” that the sear could bypass the fly.
Dang I hate this. But it is what it is.
The last “1700”/Manton flint I used was on this pistol.
(https://i.ibb.co/R04kj3n/uuid-1548-ABB7-C5-AF-4-B7-B-AFE2-3-A159-B7-ECBE1-library-1-type-1-mode-1-loc-true-cap-true.jpg) (https://ibb.co/YkTF0c9)
However:
The tumbler hole in the plate was drilled at an ANGLE so that the sear nose and notches were misaligned.
(https://i.ibb.co/3c0mX4w/uuid-425900-EF-441-C-4-DF0-9832-4-BF04-C6-DE1-B2-library-1-type-1-mode-1-loc-true-cap-true.jpg) (https://ibb.co/bXr5hQx)
(https://i.ibb.co/SXBMNGF/uuid-A36-B71-B3-5-C94-4721-88-D5-4-BB9-B9587-A33-library-1-type-1-mode-1-loc-true-cap-true.jpg) (https://ibb.co/xS6Bhdx)
(https://i.ibb.co/fdJyfXm/uuid-4-BFAA4-DD-A95-F-46-A7-ADC6-3-A48-E8-D3369-D-library-1-type-1-mode-1-loc-true-cap-true.jpg) (https://ibb.co/4RkXzFB)
Having a nice little wire welder can be a great asset.
And in my experience it is better to just fix it and get on with the build than to bother sending it back etc.
Aas a friend stated one day in conversation about such things; “You bought a casting and you did not buy a welder to go with it?” But I already had the welder.
It comes in handy for many things.
(https://i.ibb.co/b2HqfMc/uuid-DDDA6-AC0-F1-E7-44-A0-95-A5-E988357-F3-A97-library-1-type-1-mode-1-loc-true-cap-true.jpg) (https://ibb.co/s65kBd8)
(https://i.ibb.co/j35z68b/uuid-14796-AF1-2554-40-C0-A524-8-BB0-C00-D6900-library-1-type-1-mode-1-loc-true-cap-true.jpg) (https://ibb.co/p4PQ01b)
(https://i.ibb.co/HVb0Wn0/uuid-A6122-B1-C-CED9-49-AF-93-D6-BFCE9-F65-AB8-C-library-1-type-1-mode-1-loc-true-cap-true.jpg) (https://ibb.co/drVSdGS)
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Making a further comment on locks, I have always shot original guns. I've never even owned a reproduction. My favorite flint rifle was made by Henry Pratt of Roxbury, Mass. sometime after 1816 because it has one of the "Allport late with Ketland" marked locks. This was simply a better quality export grade lock. Not the cheapest but certainly not "best London" quality. In the small circle of shooters I once belonged to I was the only one that used an original rather than something newly made. My friends invariably suffered frequent miss-fires...I almost never did. Their flints wore out after 12 to 15 shots (and they assumed this was normal)...mine lasted far longer. In fact, I think I've only had two or three flints in that rifle in 30 years (although I haven't shot in a long time). None of my friends had a Bob Roller lock or I might have drawn a different conclusion but at the time I surmised that there was a great deal more to lock geometry and the balance of the springs than was understood by 99% of the lockmakers. I find it gratifying to see that this area is now being explored.
What I find most interesting is that tests I made years ago with original locks showed that the cheap ones functioned as well as the expensive ones. Perhaps they weren't as durable or quite as fast but when new any of them would have worked better than most the reproductions readily available 30 years ago.
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I contacted L&R and told him of the problem. After some discussion he wanted me to send it back. I was reluctant to do so as I don't want to pay for another shipping and still be unsure of what I'm getting back.
So they are sending me a frizzen casting that will require the hole to be drilled and the frizzen to be hardened.
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This Manton lock is a troublesome little item. I bought the recommended 5/8" English flints for it. If I install the flint bevel side down, the flint won't allow the pan to shut. If I flip the flint, the top jaw will contact the frizzen first....and still the flint will not allow the pan to close. I've placed leather on the top and bottom of the flint, but I'm using two pieces so the flint contacts the Jaw screw. (allows the flint to be as far back as possible).
I've read some other post on this lock and it appears the upper jaw will need filed back so it won't contact the frizzen.
Others have stated to heat the jaw and bend it so the jaw flats run parallel with the bolster when the lock is at half cock.
I am going to remove some material from the upper jaw. I may also remove about .200 from the jaw screw to allow the flint to set back further. That may be enough to solve the "pan open" problem.
I have a few Lyman replacement frizzers for my old T\C lock. I took the lyman and put it in the Manton. The frizzen aligns much better, but to use the Lyman it would need some filing done at the screw hole to clear the lock. Different color anyway and I don't really want to use that. But it does confirm the L&R pan cover hole was drilled incorrectly.
Live and learn. My next planned pistol build will have a Chambers.
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Dave, et al - many thanks for the discussion!