Help for a sick siler lock...

[paulvallandigham]

I use a trigger pull gauge, made by RCBS, to measure the tension on the frizzen. Just hook the wire over the top of the frizzen, and slowly pull the gauge towards the front of the gun. Watch the gauge on the scale to get the weight of tension. Always polish and buff and lightly oil the contact point between the toe of the frizzen, and the feather spring, as well as check for any rubbing of lock parts that slow the action before measuring spring tension. Some springs can be filed fairly easily, others need to be reduced by using a sander with emery cloth, moving at a slow speed, or by applying a slow speed grinder. As long as you hold the spirng with your fingers, so it can't so hot to soften the metal without first burning you, and you cool it periodically when it gets warm, You can change the demensions of the spring to reduce its tension safely.

 

[Stophel]

Now, I don't like real heavy springs myself. I like what might be called "medium weight" springs. I have never measured the weight of a spring, so I couldn't say just what weight is what. (I kinda think there is way too much measuring goin' on in modern day flintlock building anyway... :winking: ) The Siler spring is not usually too heavy, just misshapen. A spring like on some of the larger Davis locks can be absolutely horrendously heavy. (I recently worked on one Davis lock that had the most incredibly heavy mainspring I have ever encountered...I like to have never gotten it down to tolerable levels). I haven't really run across one so far that I thought was too light, but the Chamber's "deluxe Siler/golden age" one is pretty close. Some of the L&R frizzen springs are fairly light, but their mainsprings are light as well. They work well enough, and they ARE easier on flints, but I do like a LITTLE more "oomph" in my springs.

I have never been brave enough to snap a lock without the frizzen spring on it. I have always been afraid I might break something. I KNOW that snapping the cock down with the pan cover open WILL bend the cock screw and possibly bend or break the cock. I can imagine that a similar result could occur while snapping the cock down on an unsprung frizzen, which would not offer much resistance to slow the fall of the cock.

Most old locks that I have or have been able to handle usually have relatively heavy springs. I have one early 18th century German gun lock that is probably comparable in spring weight to a well-built Siler...."medium weight".... :winking:

 

[Stophel]

Another problem with the perceived weight of the frizzen spring is related to the aforementioned shape of the spring. On a spring that is shaped so that it is not very horizontal (like lots of modern springs that are slanted at a pretty good angle), the frizzen toe has to move the spring much farther than if the spring were horizontal. You are compressing the spring much more than if it were better shaped. Again, the toe has to go "uphill" as the frizzen opens, and because of this, there is also more travel in the spring. If the spring were near horizontal, all the toe of the frizzen has to do is slide across the top of the spring, without pressing it downwards very much before it snaps open. This way, even a heavy spring will feel "lighter" since you don't have to compress the spring very much at all. You can get a very positive, snappy action, which I like, without it feeling "heavy" even though the spring may be fairly stout. Very hard to describe, but if you sit and think about it, it will make sense.

 

[BLAHMAN]

(I kinda think there is way too much measuring goin' on in modern day flintlock building anyway... :winking: )

Is there any way to measure the amount of measuring that we can reliably measure so that we don't over measure?
:haha: :haha: :haha:


.....sorry, I could not resist......

 

[C_Laubach]

Take a walk down the slug gun range at frendship, and ask the shooters to allow you to try their trigger pulls. It will amaze you. The lighter the springs, the less disturbance to the rifle on firing, so that the shooter can hold on target shot after shot. The precision shooters on the slug gun line have known this for years. The slug gun guys are the Research and Development arm of black powder shooting sports. It behooves us all to be just smart enough to learn from them when we tune up our hunting guns. The feather spring's only job is to keep the frizzen closed when the gun is held in a position other than upright. 2 lbs. does that job fine. A standard test for frizzens is to remove the feather spring, and test the frizzen. It should spark, and snap open if the rest of the lock is tuned properly.

Paul,
I don't really put much belief in the "disturbance" thing and here is why. Gary Brumfield (past master of the CW gunshop) has an excellent video
of 4 or 5 locks being fired. The video has been slowed down to extremely slow speed. The one thing that I found most interesting was that at the very moment the flint struck the frizzen there was a shower of sparks following the face of the frizzen right into the pan and in almost all the cases the prime was ignited before the frizzen was half way open. So technically the gun should have already gone off by the time you claim you get this "disturbance".

There was one lock that apparently had a weak frizzen spring as the frizzen came back with great force and smacked the top of the flint. I don't think that is going to give you very good flint life. :hmm:


As for R&D the only thing I would study is the originals.........those old timers weren't dumb. They knew what they where doing.
I think some people today like to re-invent the wheel.

On to the main spring ..The main spring should have good tension. The biggest problem with the locks of today is that alot NOT ALL have improper
geometry. The main spring and tumbler should work in unison like a compound bow. In other words the cock should start out stiff and as the cock
rotates towards half cock the foot of the main spring should be coming closer to the pivot point of the tumbler, in other words it should be getting easier the closer it gets to half cock and so on into full cock. From half cock to full cock it should take vary little effort. If you study good quality originals you see what I am talking about.

Chris Laubach :hatsoff:

 

[paulvallandigham]

The tickle and rattle I am concerned about happens while the ball or bullet is still in the barrel. It affects barrel harmonics, and therefore POI, vs POA. As for the frizzen coming back to hit the flint or cock, that is a function of the geometry between the toe of the frizzen and the feather spring. If the spring is flat under the toe, it will keep the frizzen from closing up after the shot. However, if the spring is higher on the forward edge of the toe and than the back, making the toe" climb" the spring or "stack" as the frizzen opens, then you can have trouble with the frizzen going backwards, and closing with the hammer down. Please don't confuse the two errors. The light spring has nothing to do with the frizzen flopping closed. The same thing can happen with a tauter spring, if the geometry is wrong.

 

[C_Laubach]

The tickle and rattle I am concerned about happens while the ball or bullet is still in the barrel. It affects barrel harmonics, and therefore POI, vs POA. As for the frizzen coming back to hit the flint or cock, that is a function of the geometry between the toe of the frizzen and the feather spring. If the spring is flat under the toe, it will keep the frizzen from closing up after the shot. However, if the spring is higher on the forward edge of the toe and than the back, making the toe" climb" the spring or "stack" as the frizzen opens, then you can have trouble with the frizzen going backwards, and closing with the hammer down. Please don't confuse the two errors. The light spring has nothing to do with the frizzen flopping closed. The same thing can happen with a tauter spring, if the geometry is wrong.

I think you need to re-read my post .....how can the lock affect your point of aim if the ball has already left the barrel?
As for the frizzen and the rest of the lock for that matter.....study the originals. That is what we have to study not someone's opinion. You know what they say about
opinions?