Larry Pletcher
50 Cal.
- Joined
- Jul 27, 2006
- Messages
- 1,313
- Reaction score
- 67
I guess I should get into this discussion since my testing has been mentioned. The whole experiment was called "Pan/Vent Experiments", but was broken into six parts because it was easier for me to deal with. Part 6, however, deals with priming powder covering the vent. (Part 6 is at the link below, but I encourage you to look at the rest of the experiment as well.)
Part 6 - High and Low vent experiments
In the is part I wanted to see if a high or low vent position changed ignition speed. As you can see in the photos, the low vent was near the bottom of the pan. When I banked priming powder against the barrel the prime covered the vent. I did NOT attempt to work prime into the vent however. I timed 15 trials with the prime in this position as well as banked away. I also did a high vent test the same way.
After averaging 15 low vent trials were as follows:
Prime against the barrel and covering the vent --.038 seconds
Priming level in the pan --.037
Priming banked away-----.046
The high vent average when primed against the barrel was .037
There is a short video that shows the methods I used. This will give you a feel for what I went through to insure valid data.
I would also add that in my personal gun, I use a Chambers vent liner and prime against the barrel. I can see fffg barrel powder at the vent opening. My prime almost touches this. It is my opinion that two charges this close together ignite as a single charge.
One last thing I would say after doing this type of timing over 25 years is that human eyes and ears are terrible tools to assess flint ignition.
Regards,
Pletch
Part 6 - High and Low vent experiments
In the is part I wanted to see if a high or low vent position changed ignition speed. As you can see in the photos, the low vent was near the bottom of the pan. When I banked priming powder against the barrel the prime covered the vent. I did NOT attempt to work prime into the vent however. I timed 15 trials with the prime in this position as well as banked away. I also did a high vent test the same way.
After averaging 15 low vent trials were as follows:
Prime against the barrel and covering the vent --.038 seconds
Priming level in the pan --.037
Priming banked away-----.046
The high vent average when primed against the barrel was .037
There is a short video that shows the methods I used. This will give you a feel for what I went through to insure valid data.
I would also add that in my personal gun, I use a Chambers vent liner and prime against the barrel. I can see fffg barrel powder at the vent opening. My prime almost touches this. It is my opinion that two charges this close together ignite as a single charge.
One last thing I would say after doing this type of timing over 25 years is that human eyes and ears are terrible tools to assess flint ignition.
Regards,
Pletch