SpudFiles

Oh wow, I should really pay more attention... I've been using polypropylene all along. Great stuff, apparently, and cold resistant, which is great up here in Finland

jimmy101 wrote: Absolutely. I don't believe anyone has ever measured the precise affect of running the chamber fan during firing but it is generally believed that it will boost performance. So, wire up the fan and leave it running continuously throughout your firing session.

I have my fan on my advanced combustion wired to 18V instead of the normal 12V, but the fan can take it, but still I dont leave my fan running the entire time. After a shot I open the exhaust valve take my barrel off th reload. byt the time i've reloaded a golf ball and strap the barrel back on, which with cam locks takes all of 10 - 15 seconds, the chamber is vented and i kill the fan and close the valve. i then meter my propane inject it and then kick the fan on for the shot which i leave running for the shot and then right back off. saves me from running through batteries as quickly.

My chamber fan's frame broke at two places...

A 20lb propane tank would last, well, lets see, I would say it will last until October 31, 3245. A 20lb tank would be something like tens of thousands of shots from your gun.

The problem you are having is that the amount of fuel is not consistent from shot to shot. Liquid fuels have to vaporize and then mix with the air in the chamber. The vaporization step is not consistent. On a hot day alcohol will work much better than on a cool day. The amount of liquid fuel required for your size chamber is very small. This page has more info on using liquid fuels in a spudgun.

Also you need to realize that there is a correct amount for whatever fuel you are using. Too little fuel will perform poorly or won't ignite. Too much fuel also will perform poorly or won't ignite. More fuel is not better, you need to get the correct amount every time.