Noob to combustion

[Puppet]

Hi everyone. I am currently in the process of building my first combustion spudgun. This will not be my first cannon however as I have built a .50 cal air cannon in the past. I have a few questions i want to get answered before i put it all together. Here are the parts I have:
5 feet of 2" pvc pipe
5 feet of 4 inch pvc pipe
4 inch to 2 inch reducer
4 inch cleanout cap and plug
lantern lighter

1. What is the best chamber to barrel ratio for a 2 inch barrel using spray deodorant (old spice or right guard) as a fuel?

2. My 2" pipe doesnt fit perfectly into my reducer (not toght but not loose either, kind of semi-snug) will this be okay when I pvc cement it together?

3. What length barrel do you suggest I use ? I was thinking 3 to 4 feet.

4. Where should I mount the lantern lighter?

Any help you could give me would be much appreciated. Thanks!

[singularity]

1 dont remeber probally doesnt need to be presise

2 - youll be fine as long as you know how to use pvc cement

3 - well mines got a 4 foot barrel (its just a combustion +/- a foot probablly wont make much of a difference

4 - well i made a front grip for my cannon and i mounted the ingnitor there

ps - i see yuor up a midnight too yay for insomnia (unless your in a different timezone)

[brumby]

1. the best chamber to barrel ratio is 1.5:1 ... so you could do a 5 foot barrel and a 23.75 inch chamber

2. ditto on the guy above me

3. thats up to you.. 3 - 4 feet is fine go to http://www.burntlatke.com/ratcalc.html to figure out your C/B ratio

4. sorry im no good with lantern lighters but its best to drill through 2 layers of plastic, so i would put it towards the back at the cleanout plug.

With a combustion the first and best upgrade you want will be a chamber fan go to http://www.burntlatke.com/fan.html to find out more

[frankrede]

Her is how I made mine.
It gives it a nice clean look.
[albumimg]231[/albumimg]

[Hakaro]

hey did you guys here about right guard it sucks that it happened I loved using it for my propelant I just ran out like twenty minutes ago!

[MrCrowley]

yeah its been on the homepage for months now