First Potato Gun "improvements/feedback"

[battlelava]

Well im starting my first potato gun and i want to start off somewhat complicated, with a semi realistic looking "ww2 howitzer" style. I'm going to give it a 60" long 2" sleeved barrel and a 20" long 3" combustion chamber and it should look like something like this and gives me about a 1:1.5 ratio if I remember correctly.

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(yes i know how poor these sketches look) I should have some better design sketches to post up tomorrow as i quickly made this on some weird 3d program.
After which I'm going to find a nice mount to attach it to to give it an authentic look, in which I'm going to mount it on a hinge and a front "lift" with some threaded rod. I'm 99% sure of how to do all the internals (sparking, mixing fan ect) but I was looking for feedback on the design

[jackssmirkingrevenge]

For an authentic howitzer effect, I would leave the barrel and chamber on rails and have them free to recoil, anything from bungee chord to an automotive gas ram would suffice as a recuperator

[battlelava]

I was thinking of that but I'm not sure it has enough of a kick to move it back
but I defiantly want to incorporate it in.
This wasn't my original design but i'm going to stick with this one, the all mighty Flak 18/36/37/41 88mm because of how amazing it looks (and how i got a much more clear design

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I wont be able to make it out of metal due to limited tools and materials(only got a acetylene torch, saw, and a drill ) Besides shooting it for fun maybe i could use it in airsoft simulation with some sort of powder bag to shoot that explodes right after it leaves the muzzle for some cool effects.

[wyz2285]

I really like to see this thing finished
But if you have enough balls I would suggest a hybrid for a realistic fire and recoil too

[battlelava]

I'm thinking about that but I don't have a clue how hybrids work and I don't know how easy it would for me to build it out of all metal do it wouldn't self destruct ad I font have access to a welder or high amounts of metal if anyone could point me in the right direction I would gladly make it a hybrid although it might take me forever to mae

[wyz2285]

here is a well made hybrid, you just need to build a recoil absorber and a base to compleat the look

[pneumaticcannons]

The recoil should be sufficient when using spuds or heavier projectiles. Anything with a 2" barrel should kick quite a bit. I'm excited to see this one finished

[battlelava]

Well as of right now i was going to shoot golf balls through it because I've got enough of them to supply like 10 driving ranges, although i might change it to shoot soda cans filled with some type of weight (probability concrete). I am going to defiantly make it a hybrid but its going to be a burst disk, maybe 10-15x? If I go with soda cans i want them to really fly and I dont know how much power is needed or how much is given off per 1x. And no because im making this into a hybrid how can i get this moved into the right thread?

[Gun Freak]

1x is ~100 psi. I think 10x is overkill. Let's not even speak of 15x. Or hybrid for that matter

[battlelava]

Could a properly fueled combustion cannon launch a soda can filled with concrete very far say 250m?

[Gun Freak]

I'd say no, because soda cans are heavy and not exactly made for flight. But I'm assuming you don't mean a combustion that is 20 feet long.

Speaking of...

[Mr.Tallahassee]

With the chamber you have and a 3'' SCH80 barrel at 60'' length you can launch a concrete filled soda can in a sabot as far as appox. 530 feet at a 43 degree angle according to HGDT. The chamber fan only makes a few feet in difference as well.

[battlelava]

Is that with a combustion? Or a hybrid ?

[mattyzip77]

Looks great in the pics posted, however lets see it when its done. This looks like a long process, however the finished product will be worth the wait.

[battlelava]

Got some quick sketches ill post when I get to my computer just have to rough sketch a recoil mechanism. Any ideas[/code]