SpudFiles

I just bought this at wal-mart. It serves both as an adjustable regulator, and it attaches directly to disposable propane bottles. It's outlet is 1/8" FNPT. It comes with a threaded pipe and some sort of white gas fitting. This is for camp stoves, but it seems like it should work great. It cost just under $20 after tax.

ooo, i think i will have to look for that the next time i go to walmart

It's nice eh, It's like two parts in one. 'Course now I have to go buy a new hose barb that fits this. I'm glad I can turn off the propane flow at the bottle so I won't have pressurized propane in the hose leading to my meter.

I looked on the walmart website and I cant find this, can you shead some light on this?

And is there and kind of valve inside the 1/8" FNPT side of it?

It was in the camping section of my local Wal-Mart.
There is a website on the packaging www.centurycamping.com
That thing on the pipe end isn't a valve, it's just a useless spring that is probably useful when you are using this for what it's made for.
Opposite of the FNPT side there is an adjustment knob, but other than that no valves.

Those regulate down to .5 psi, don't they?

i was at wall mart yesterday to buy airsoft bbs, and they had absolutely none. completely out of stock or just too lazy to restock. either way i was pissed. so now im putting a jihad on them, jk.
anways
can you regulate the pressure or just the flow rate?

yes you can regulate the flow rate, you can do this by how far you open the knob on the side of the propane imput.

It's adjustable up to 20 psi. This is a little low for my meter, so I just do three quick injections. It takes more actual knob/lever turns than before, but it allows me to load much more quickly because I don't really need to keep my eye on the meter gauge. This is an actual pressure reg, not a flow reg.

why not get a real regulator for the outrageous price of 18$? and ise that thing you have now for the propane fitting

I'm not sure what pressure you think "real" regulators operate at, but they generally are fixed at 20 psi.
I've seen high pressure regulators online (mostly 30 psi, a select few go as high as 60 psi), but they cost quite a bit more than $18, especially ones with adjustable output.
A 0-60 psi adjustable regulator would be ideal for my cannon, but propane gas regulators of that type can be hard to even find online (I really prefer to buy locally). It would require more fittings to adapt to disposable bottles.
This regulator is super compact because it attaches directly to disposable propane bottles which is perfect for me because I'm using on-board metering and propane storage.
It would be nice if this regulator could output up to 60psi, but I'm pretty sure no such fitting exists.

By real regulator I meant an air regulator. with an adjustable output up to at least 100 psi.

Every air regulator I have personally seen dumps excess pressure into the atmosphere, this is safe for air because it's not explosive. I personally don't think standing in a cloud of air and propane while firing a combustion cannon sounds like my idea of a good time.
I know there are some non-relieving air regulators out there, but they can be hard to come by and they are definitely not intended to come in contact with high pressure liquid like can happen when you compress propane. A CO2 regulator would probably work great, but again too expensive for me.

They only release air when you set it.
once you set it at the right pressure, it shouldn't release any air.
and thats what most people use, and I have yet to hear of a regulator catching fire.
And I doubt that the small amount of gas woul reach the barrel to ignite before the gas had already dissipated into the atmosphere

Well I'm perfectly happy with just using a propane regulator.