kaintuck said:
I find if I drill the touch hole with a helical sprial hole, the vortex creates a column of fire, then that intern, will light the main charge faster than a standard drilled hole flash.
The venturi touch hole has the second highest speed in lighting a charge of black powder.
I will do further studies as soon as my fingers heal up, the grafts are doing well, and doctors tell me i will have most of the feelings back after my re-hab.
The word Venturi came down to us from the Colonial days.
A man named Venturi was getting irrigation water from an irrigation system, which all had outlet holes of the same diameter. However, it was found that he was getting more water from his same size hole that anybody else was, but still paying the same fee, as all the other customers were.
An investigation found that he had coned his outlet hole from the inside, which allowed increased water flow in this instance. That coning procedure is now called a Venturi. All carburetors and fuel injections now have them on the air side of the vehicles fuel distribution system.
And Venturi is also used any place an increase in flow velocity is desired.
A Venturi, a coned hole or passsage, causes more flow by speeding the velocity of the air passing through the Venturi. The velocity increases the temperature of the flame front, in the case of our flintlock rifles. This should cause the powder charge to ignite more quickly due to the increased temperature of the flame front.
If the touch hole is coned from the inside, the velocity will be decreased and the flame front temperature will be decreased.
Obviously, it would take very precise models and instrumentation to detect any of this.
What will I do to my rifles? I will cone my touch hole liners about half way through, from the outside. What degree of cone will I use? Probably a 45 degree cone will work well. It's not the diametric size of the cone, it is the angle of the cone.
What size will I make the holes in the touch hole liner? That is going to take some careful experimentation. I suspect each rifle might exhibt a preference for minutely different size tough holes.
Whe I was young and building hotrod chevy and ford engines, and racing those vehicles, I knew about Venturi and his scam with the irrigation water. I gave the exhaust ports a slight venturi effect in the direction of exhaust gas flow. The dynamometer said that was worth 25 extra horse power to the rear wheels. I had other legal racing procedures that I ground into the mix too.
Each pipe on my headers had the outlet squeezed down where they went into the collector. Instead of increasing back pressure, this helped scavage exhaust gases from the headers into the collector.
People would protest me. My engines would get tore down and nothing illegal was ever found. I only told Ed Iskenderian what I was up to, and he never told anybody else. However, I did get free dynamometer time on Ed's dyno... Ed is now, ninty-eight years old and still works every day!
My cars were always very fast. At the local strips where I raced, I was nearly always top eliminator in my class. Therefore I have had some experience with old Venturi and his irrigation water scam...
Bill
