Need help Mini pill bottle combustion cannon 1st

[Benjg555]

Hey you guys going to build my first mini. Well first of the supplies that will be used:
Pill bottle
Bic pen tube
Some type of gas, bic lighter fluid,bug spray or hair spray any other good ideas will be helpful.
Ignition source is still unknown need help on igniting it. I Was thinking about making a sparker but then that'll make it bigger so probably not.
Any ideas please you guys cmon need a way to spark/ignite the fuel.
Ammo: whatever fit in the tube

For the back of the pen tube maybe pinch it a little bit so ammo doesn't fall back into the pill bottle. Or would that restrict the flow of the combustion going into the pen tube?
I will be uploading pictures of the pill bottle and pen tube later

Thank you :occasion5:

[qwerty]

Right, mini pill bottle guns are usually very inefficient so first of you shiould try starting with something a little bigger like a 500ml coke bottle or some PVC fittings. For the igniter? well your best bet is to buy one of those little long-nosed ovenlighters and take it apart.

Chop the two wires from the little sparker so you have a few inches left then take it out. You now have a source of ignition

PS: you can also use the little butane tank inside too, to get morwe accurate fueling if you're still making a little combustion.

[Benjg555]

Ya maybe I will I think I have an idea for one

Alright I'll have to go out and get one
You have a pic with the sparker and butane?