Firing problem

[Pete Zaria]

Just for comparison, on my old cannon (ABS combustion with 250ci chamber, no propane meter), I use 6-7 seconds of propane from a reasonably fresh tank and benzomatic torch head. I wouldn't think you'd need more than 10 for a 350ci chamber.

Propane is heavier than air, so when fueling, you should point the barrel downwards and put fuel in from the cleanout in the back.
What I do is open the valve and stick the torch head down inside the chamber, count to 7 or 8, pull the torch out, replace the cap, turn off the torch, aim the barrel upwards for a few seconds so the propane distributes around the chamber, then aim and fire.

Another possible problem is that the propane isn't mixing with the air very well. Putting a computer fan ($3) in the chamber solves this problem. Look around the site for insturctions on wiring it, but it's pretty self explanitory. Don't bother with a timer circut, just use a momentary on switch.

How many spark gaps do you have, and where in the chamber are they placed?

Good luck.

Peace,
Pete Zaria.