Steve and I completed the testing that was meant to accompany the percussion tests we did this past May. At that time we reported the results of timing the small Siler percussion and the mule ear with the same lock plate. We now can add the results of the two small Siler flintlocks. Each lock was lubed, and a new flint was installed. A Chambers 5/16 liner was installed in the barrel. The photos shows the fixture with a flintlock installed and ready. (You may not be able to see, but the liners used in these tests were equipped with two small holes drilled in the surface so that a spanner wrench can be used to do rapid changes. This idea came from Dan Pharris who helped in the earlier breech tests.)
The methods used remain the same. To summarize, a contact is placed below the sear so that when the solenoid strikes the sear, it closes the contact and begins the computer’s timing routine. A photo cell located at the muzzle stops time. This means that the time we measure includes:
a. lock ignition
b. barrel ignition
c. barrel travel time to the muzzle
The only variable that is changed here is the lock.
As before the test includes 15 trials for each lock with averages calculated. The chart below shows the results. I included the results from the percussion locks to make comparisons easier.
Mule Ear-----------S Siler Perc. ----------stock Siler Flint ---------Mod. Siler Flint
.010--------------------.011 ---------------------.068 ---------------------.072
.014--------------------.012 ---------------------.068 ---------------------.066
.010--------------------.010 ---------------------.059 ---------------------.068
.016--------------------.010--------------------- .060 ---------------------.072
.010--------------------.010 ---------------------.071 ---------------------.072
.011--------------------.010 ---------------------.066 ---------------------.071
.009--------------------.012 ---------------------.069 ---------------------.078*
.019--------------------.010 ---------------------.062 ---------------------.044**
.023--------------------.008 ---------------------.059 ---------------------.064
.009--------------------.012 ---------------------.086*--------------------.065
.013--------------------.025 ---------------------.071 ---------------------.056
.019--------------------.013 ---------------------.069 ---------------------.075
.016--------------------.009 ---------------------.090*--------------------.062
.010--------------------.012 ---------------------.076 ---------------------.070*
.016--------------------.008 ---------------------.073 ---------------------.071
------------------------------------------------------------------------------------
.0137------------------.0115 ---------------------.0698-------------------.0671 (avg)
* --- Indicate knapping flint
** --- In this trial the photo cell may have triggered on the pan flash instead of the muzzle. The time is a reasonable for the lock by itself.
Temperatures during the percussion test varied from 56-60 degrees, and humidity dropped from 60 to 42% during the testing. Yesterday during the flint tests, the temperature was 68 degrees and the humidity 60%.
Drawing conclusions remains somewhat sketchy at best. A few things need to be mentioned first. The data was drawn from only one of each type of lock. Would a different mule ear, or a different stock small Siler, or a different modified Siler have changed the results; I don’t know. So we must qualify any conclusion by admitting our data comes from only 4 locks. With that in mind, a couple of things stand out in my mind.
First the modified flint Siler’s performance was only marginally better than the stock Siler. I expected a larger difference. Perhaps bells and whistles don’t actually improve the actual numbers but only our impressions. We think it must be faster because it has a roller frizzen, for instance.
The mule ear lock was not faster in this test than the side-hammer lock. This was a surprise to both Steve and me. We expected the short throw to mean faster times; maybe the throw was so short there was no distance to accelerate. (The spring was VERY stiff. More thinking is needed here. Can a mule ear’s throw be so short that it doesn’t have space to accelerate?)
At first glance, the difference between the percussion and the flint trials was larger than expected. After thinking about earlier tests, these numbers seem typical. Consider that times recorded for Siler locks in many previous tests run from .0370 to .0450. My test bed Siler was consistently under .0400. We timed barrel ignitions a number of times between .036 to .046. ( I included the .046 for those who bank their prime away from the barrel. If you prime next to the barrel .036-.038 is a better figure to use.)
If you add the lock time to the barrel time (.0370 + .036), our numbers seem to fit. This addition makes me think that time measured from sear to muzzle in the .060 - .075 range are typical. I might add that in adding these together we are including the pan flash twice:
<-------------sear to pan ignition--------->
<-------------pan ignition to muzzle------>
Since I have to use a photocell to start and stop the time, I can't avoid including it in both times.
From the data we gathered and using the limited number of locks, it would be safe to say that percussion ignition is about 3-4 times faster than flint. The numbers could be interpreted more tightly than that, but the variables involved with flint edges, when you choose to knap, etc, make me hesitate to do so.
Here is the overall equipment. The Apple IIe and interface are in the background, with the fixture in front.
![](https://americanlongrifles.org/forum/proxy.php?request=http%3A%2F%2Fi93.photobucket.com%2Falbums%2Fl72%2Flpletch%2FPistol%2520Lock%2520Tests%2FIMG_3206.jpg&hash=ba00527ad309bc63a7811bfd87fb5fe97de43a52)
The fixture here has the flintlock installed. Omitted here is the wire tie that was used to retain the barrel.
![Smiley :)](https://americanlongrifles.org/forum/Smileys/default/smiley.gif)
The pistol is rotated up on the steel pin for cleaning and loading.
![](https://americanlongrifles.org/forum/proxy.php?request=http%3A%2F%2Fi93.photobucket.com%2Falbums%2Fl72%2Flpletch%2FPistol%2520Lock%2520Tests%2FIMG_3210.jpg&hash=f38c434a523ea4cb34f9b335a44eead56e21a2e3)
Looking closely you may see the three holes in the liner. The outside two are for the spanner wrench.
![](https://americanlongrifles.org/forum/proxy.php?request=http%3A%2F%2Fi93.photobucket.com%2Falbums%2Fl72%2Flpletch%2FPistol%2520Lock%2520Tests%2FIMG_3208.jpg&hash=bcca7e08631580d95880d8b207202135664b5b30)
This shows the contact below the sear. The solenoid closes the contact when the sear is triggered. The other end of the contact is attached to the lock-retaining screw.
![](https://americanlongrifles.org/forum/proxy.php?request=http%3A%2F%2Fi93.photobucket.com%2Falbums%2Fl72%2Flpletch%2FPistol%2520Lock%2520Tests%2FIMG_1855.jpg&hash=e453cec35e1c702ef829e03082d60dfd557090c4)
Here is the photo cell that triggers on the muzzle flash.
![](https://americanlongrifles.org/forum/proxy.php?request=http%3A%2F%2Fi93.photobucket.com%2Falbums%2Fl72%2Flpletch%2FPistol%2520Lock%2520Tests%2FIMG_1858.jpg&hash=69c059e58c494330d3dca6132e7d5daa11229e51)
I hope this all makes sense. I'll probably get this together from beginning to end on my web site. I'm uncertain as whether to send this to MB.
Regards,
Pletch