Flint chipping/breaking fix - "Hard on flints"

[Marcruger]

Hi folks,

I was speaking with Lowell Haarer at the New Market show this weekend.  We were discussing locks, and the topic of breaking/chipping flints came up.  It occurred to me that maybe some of y'all haven't heard of the trick I learned, so I will share it here. 

In talking with folks and researching why some locks are hard on flints, I repeatedly heard that "balancing" the power of the mainspring versus the frizzen spring is the cure.  I don't doubt this, but I am certainly not a builder like many on here......nor am I the great Jim Chambers!

In one book I read that one reason that flints get chipped/hammered/broken is that the frizzen actually bounces bad after opening, hitting the resting flint in the cock, and effectively knaps the edge of the flint.  It sure looked like the description of what my Late Ketland was doing to the flints.  I was losing flints at a fast rate. 

The solution in this book (I don't recall which right now), was to simply extend a piece of flattened lead ball out to the end of the flint on the top side.  This takes the blow from the knapping frizzen thereby stopping the issue.  I use leather in the jaws, so I experimented with longer leather on top. 

VOILA!  Problem solved.  The current flint you see is an old one, but keeps on sparking like mad.  It feels a little dull, but the gun goes off "right now". 

Thank you Lowell for asking me to share this. 

BTW, Lowell makes some beautiful rifles, and I got to handle a few at the show.  Well done, well balanced, and finely detailed. 

Best wishes and God Bless,  Marc

[Marcruger]

My apologies for the poor quality photo. 

[P.W.Berkuta]

Interesting -- sure does look like it can solve a problem. Maybe a lock tune-up can solve it also. I like the leather idea as a quick fix.

[oldtravler61]

  Marc thanks for the tip.  Oldtravler

[gumboman]

Many thanks for that tip. I have been aggravated by a Davis Twigg lock that gobbles up flints. After reading your post I videoed the lock and played it back in slow motion on my computer. I can clearly see the frizzen rebounded just as you said and slammed into the flint before going fully into the fired position. It was an epiphany for me as I now realize why I can get only single digit firings from a flint before miss fires begin. After 4 test firings it was obvious the new very sharp flint was knapped and had lost its keen edge.

Will definitely try the extend leather tip with hopes of solving this exasperating problem.

[Bob Roller]

This is one of the oldest flint savers we have and Lynton McKenzie told me about it
in the early 1970's.

Bob Roller

[Bob Roller]

Many thanks for that tip. I have been aggravated by a Davis Twigg lock that gobbles up flints. After reading your post I videoed the lock and played it back in slow motion on my computer. I can clearly see the frizzen rebounded just as you said and slammed into the flint before going fully into the fired position. It was an epiphany for me as I now realize why I can get only single digit firings from a flint before miss fires begin. After 4 test firings it was obvious the new very sharp flint was knapped and had lost its keen edge.

Will definitely try the extend leather tip with hopes of solving this exasperating problem.

The Twigg has a cam on the frizzen spring and this can be altered a bit to get the
sweep of the cock and the ignition back into proper time.I made a group of about
14 of these big Twiggs and never had a reported problem of this kind.

Bob Roller

[Acer Saccharum]

The Twigg has a cam on the frizzen spring and this can be altered a bit to get the
sweep of the cock and the ignition back into proper time.
Bob Roller

Bob, when you speak of getting the lock back into proper time, does it mean that the cam can be altered or re-located so the frizzen flips over easily, and is hard to close?

[Flint62Smoothie]

Hmmmm ... I guess someone could also put blue tape or something else (?? ... any ideas?) on top of the flint to see if there's any visual evidence of the frizzen banging back down onto the top of the flint? Maybe it would leave an impression in soft leather that was dampened?

[gumboman]

I tested this out today. Cut a larger piece of leather and placed it so that it was just to the cutting edge of the flint. Took another video. Slow motion playback revealed the frizzen bouncing back after first strike, making contact with the leather and flint underneath,  then returning to the open position. The leather is now a cushion. Because the leather is new and unused it has some stiffness to it so there is a slight gap between the top of the flint and the leather. Slow motion is amazing and it revealed the leather being struck, then being forced down on the flint by the frizzen and then moving up after the frizzen bounce back. This movement appeared as a spring would look when being compressed then released. Of course it is only leather but the movement of the leather makes it look like a leaf spring in slow motion.

After watching the video for 10 or more times, I am certain beyond any doubt the problem with this lock greedily consuming flints is the rebound. The video reveals the truth clearly. It also removes any doubt the geometry is wrong on this lock. If my memory is correct, I read somewhere this lock was copied from an original. If this is accurate,  then we can safely make the assumption the lock makers of old could not see this error in lock design.

Marcruger, thanks a bunch for your post and photo. It has been immensely helpful to me in solving a nagging problem. I will also video my Chambers and L&R locks the same way. Could be interesting to see what that might expose. Will also be fair as I don't want to unfairly criticize the Davis lock if the other brands do the same thing.

[sqrldog]

If you want to check for flint rebound put some transfer color on the back edge of the frizzen if it rebounds it will make a transfer mark on your flint. Old lipstick works well.  Tim

[Acer Saccharum]

I had a lock with a similar problem. The mainspring was so strong, it self-knapped 1/8" off the flint edge at each firing. Shards of flint flying, pan with several large chunks of flint in it.

i tried everything I could think of with the frizzen spring, reshaping, opening it more, to no avail. I even curved the frizzen face more, thinking it might be more conducive to a sweeping, shearing motion. In the end, I ground thickness off the Main spring leaves to reduce its power.

[bgf]

I learned about this years ago, first on here from Dan Phariss if I recall correctly.  It works well, at least until the root cause is found and corrected.  My Durs Egg first was bad to break flints, then the problem almost went away but came back as the frizzen spring got fatigued and very light.  It is non-issue with new forged main and frizzen spring, even though they are MUCH faster, so I tend to believe the "balance" theory.  An early model Chamber's late ketland on my chunk gun has never broken flints, despite having a really strong mainspring and stiff frizzen.

Thanks for posting real life experience!

[Marcruger]

I am sure this "trick" was invented back in the 1700s, and it was certainly not my original idea.  I am glad it may help someone.  I assumed it was common knowledge until this weekend. 

The reason for the original book suggesting lead instead of leather is that it most likely better conforms to the flint and doesn't bounce around.  The book did suggest that you can see the imprint of the frizzen in the lead if that is the cause. 

I guess tape would work as a test, but seems less "PC" than leather.  ;-)   Hah, hah. 

Even though mine seems to curl up due to shooting and cleaning, it seems to do its job. 

That Late Ketland is indeed a fast lock and I'd own another in a heartbeat. 

Best wishes and God Bless,   Marc

[Bob Roller]

The Twigg has a cam on the frizzen spring and this can be altered a bit to get the
sweep of the cock and the ignition back into proper time.
Bob Roller

Bob, when you speak of getting the lock back into proper time, does it mean that the cam can be altered or re-located so the frizzen flips over easily, and is hard to close?

I had one of the Twiggs in my shop years ago that I altered the cam a bit by sloping  both angles
and making the frizzen easier to open AND close.This lock had the "as cast" internals.
Recently I looked at an L&R set of external parts and wondered if any thing can be done about
the appearance of the frizzen spring and when looking at the frizzen spring from the Chambers
late Ketland I think it may be interchangeable.I will post on this when I actually try it.

Bob Roller

[gumboman]

Sqrldog, the old lipstick on frizzen cover is a good idea. Will try that too.

I am ready to order some locks. Let's talk.

[Dphariss]

I have a "Manton" lock made from castings and I ended up making a mainspring and link. I set it up for a strong mainspring and a strong frizzen spring so the flint scrapes it well. Frizzen is easier to close than open. Its not all that hard on flints. Often eating flints comes from a frizzen being a hair too soft so the flint digs in too much.
On a hunting gun having a frizzen that moves too easy can cause the pan to be empty when you want it full...
There are many things other than springs. The angle the flint strikes the frizzen etc etc.
Handled a Manton shotgun the other day. Probably 1800ish... Strong springs even today.

Dan

[Dphariss]

A weak opening frizzen can also result in it having a lot of extra speed imparted by the cock....
There is no pat answer.
I would also point out that locks copied from originals are prone to losing something in the translation or due to the current day maker thinking he is smarter than the original lock filer.
Dan

[Dphariss]

Its also worth noting that the late English locks had smaller cocks and frizzens than earlier or other European or military locks.
Every lock design seems to be its own rule to further muddy the water.
Locks with bigger cocks and such can get good performance with lighter springs. Though it does lengthen the lock time.
The English really worked on the FL, surely due to all those Peers of the Realm and landed gentry shooting flying birds and their best locks of 1800-1830 were hard to beat. They were trying for speed and CONSISTENCY to allow flying birds to be lead properly. The late Manton lock makers (who ever they were) flintlock internals were used on percussion and brass suppository guns virtually without change.
Dan