Testing a lock

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Commodore Swab

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Not something I do on all locks but when tuneing and tweaking locks should some desire a reliable lock this is how it goes:

Install clean ready lock in vise and prime

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Fire the lock igniting the powder. and reprime without cleaning and attempt to fire again. To pass the test is 20 test firings without cleaning or removing any residue. 20 shots must be fired with 90% or better reliability to pass. The lowest passing score is 20/22. If you must reprime automatic fail, knapp flint automatic fail, clean automatic fail. After 20 shots the flint can be chipping the residue builds up and with no barrel charge you don't get that blast to clear either making this a more brutal test than just 20 shots.

After 20 firings the lock appears quite dirty but with a perfect score 20/20 I will decide to see how much farther it will go before a misfire.
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Continuing on with the lock in a mess like this another 14 ignitions went perfect misfiting on the 35th. Closing the frizzen and reattempting on 35 without repriming she fired. All in all a very successful brutal test. Some final pictures after the test.

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1950DAVE

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35 flashes in the pan makes her an ugly gal. She needs a trip to the beauty parlor.
Dave
 

Commodore Swab

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Tip #1 for reliability most all locks have springs that are too hard. They work great for a few shots and great for hunting when you have time to clean and prep before the next shot.
 

Bnewberry

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I take your meaning as the springs are too strong. Does this make the lock chip flints prematurely?
 

Commodore Swab

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Yes, It's common to have a good sparking lock but the question comes how long will it continue to spark good and will buildup effect the operation
 

Rusnapperhead

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Interesting test; what type and how much priming powder.
Mine does not lift the frizzen when firing; suspect too much spring. I need to do more research on where to file and sand to lessen its power. Or just leave it alone and keep shooting it🤔
 

Commodore Swab

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There is no "measure" of powder as not all pans are equal. I measure FFF until the pan for that particular lock is flush with the top of the pan. Some take 3-4 grains and ive had large ones take as much as 15+
 

Larry (Omaha)

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Not something I do on all locks but when tuneing and tweaking locks should some desire a reliable lock this is how it goes:

Install clean ready lock in vise and prime

Fire the lock igniting the powder. and reprime without cleaning and attempt to fire again. To pass the test is 20 test firings without cleaning or removing any residue. 20 shots must be fired with 90% or better reliability to pass. The lowest passing score is 20/22. If you must reprime automatic fail, knapp flint automatic fail, clean automatic fail. After 20 shots the flint can be chipping the residue builds up and with no barrel charge you don't get that blast to clear either making this a more brutal test than just 20 shots.

After 20 firings the lock appears quite dirty but with a perfect score 20/20 I will decide to see how much farther it will go before a misfire.


Continuing on with the lock in a mess like this another 14 ignitions went perfect misfiting on the 35th. Closing the frizzen and reattempting on 35 without repriming she fired. All in all a very successful brutal test. Some final pictures after the test.
Neat testing, but I have two questions that come to mind
1. How can reliability of a lock have anything to do with residue build up? If the residue (and it does) cause low or no spark, how can you blame the lock?
2. I use good black English flints, but they are like money, not all are equal. You have a flint that flakes a third of its' body and now you blame the lock.
Don't get me wrong or think I am being difficult, I am trying to understand the logic here.
Thanks for a nice post!
Larry
 

Commodore Swab

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Neat testing, but I have two questions that come to mind
1. How can reliability of a lock have anything to do with residue build up? If the residue (and it does) cause low or no spark, how can you blame the lock?
2. I use good black English flints, but they are like money, not all are equal. You have a flint that flakes a third of its' body and now you blame the lock.
Don't get me wrong or think I am being difficult, I am trying to understand the logic here.
Thanks for a nice post!
Larry
Fair questions.
1A Some locks will stop working with little buildup some it takes much more to become an obstruction. If the springs are too weak the buildup will result in a lock that builds up and stops working fast. Springs too strong will quickly dull the flint. In both regards a "clean" lock will not show any difference.

2A If a flint has a crack that causes it to break catastrophically I can see that and adjust. Before the test they are typically a few sparking to insure that will not happen. When a flint dulls too fast it rarely is a fluke although I will if I must try a second and third. When one dulls fast 9 times out of 10 the next one and the third will do the same signifying a different problem. When that is corrected I have gone back in the past and reknapped one of the offending flints and had it pass without a problem. Naturally if someone puts an incorrect flint in the reliability will be in doubt. I assume in the future correct flints will be installed.
 

Col. Batguano

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That's a neat test.

I would add in a first step before performing it though;

Step 1.) Disconnect smoke alarm! (or open window and turn on a fan)
 
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Commodore Swab

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I hope you have some lead or copper vise pads around the lock plate..
I don't worry about that at this stage. If I need to be careful I have bronze pads. When Im all done I will need to tear it all apart and polish it.
 

LRB

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Interesting test; what type and how much priming powder.
Mine does not lift the frizzen when firing; suspect too much spring. I need to do more research on where to file and sand to lessen its power. Or just leave it alone and keep shooting it🤔
Beware. It is not uncommon for some locks to allow the frizzen to bounce back, and it happens to fast to see it. Put a smear of lip stick under the tail, snap the lock, and look for lip stick on the spring. The cure, if that is what is happening, is to remove some metal under the tail to allow it to open more. If your lock is firing, but the frizzen isn't open, there is a good chance that is what is going on.
 

ord sgt

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The frizzen and spring play a big part in the wear and tear of the flint. The frizzen should rotate smoothly, providing enough resistance against the flint edge to create a good shower of sparks. Some frizzens have a roller riding on the spring. Others just have a foot, which if smooth, glides over the spring. A frizzen, if heat treated properly will last quite a long time, throwing enough spark to light off the pan.
 

Commodore Swab

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I extended it out over 100 attempts I knapped it twice cleaned by just rinsing 3 times. I never reprimed and overall it misfired 9 times. Cleaning, oiling, and knapping the flint she passed the test again with 1 misfire for a score of 20/21. So far that means the flint has been used for 120+ firings and is still throwing sparks and igniting a dirty lock

I think it is safe to say this lock is relatively gentle on flints
 

dave_person

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Here is a test for you. The flint is put in place backwards with the dull blunt side facing out.



Then I found a rounded piece of quartz in my drive way.



Really good lock. It happened to fire 671 rounds without a single misfire or hang fire and used up 10 flints. Strong springs but well balanced.

dave
 
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