SpudFiles

I'm trying to build an airsoft mortar/spread launcher. I made a simple pneumatic cannon (2 feet of 2" PVC, tire fill valve, 1/2 ball valve and 1 foot 1/2" barrell) which originally I used to shoot marshmellows, but found it works ok for airsoft BBs. My first question: What is the best type of manual pump to use? It needs to be portable, preferably a foot pump, and needs to be able to do 80-100 PSI. My current bike pump can only do ~60 PSI. My second question: What barrel size should I use? I'm shooting a blast of BBs in the air like a mortar, with an optimum spread of 10 feet. Is 1/2" PVC the best choice, or should I go to copper pipes? Thanks!

Just because your bike pump says it will do 60 PSI that does not mean
it cannot do more. Also for that pressure copper is overkill so
1/2 inch PVC shoud do.
I'm not going to tell you to use sprinker valves or piston valves
but they will help. If it work for what you want there is no reason
to upgrade.

I've tested and it can't do more than 60 PSI.. cheap pump. Is there an air pump you reccomend?

It depends, if budget allows and you have a 12v battery, try a car tyre
pump. If you don't want to have to depend on a car battery, ask
at a bike shop. They should have a pump that will get 100PSI.
I'm not referring to a shock pump but a good one is worth about
$15 AUD $10 USD.

For the pump use a bell. I got one at walmart for 14 bucks. Its got a 1 to 200 psi gauge and can go up to 120.

That sounds good. Maybe I'll have money left over after buying Christmas gifts. Thanks!