pnumatic spud guns

Boom! The classic potato gun harnesses the combustion of flammable vapor. Show us your combustion spud gun and discuss fuels, ratios, safety, ignition systems, tools, and more.
quinn whitsitt
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Sun Feb 11, 2024 7:49 pm

i need some advice on how to build pnumatic spudguns i am wondering how i whould build a fully auto air spudgun that dose not loose pressure when it shoots and that has a very fast almost bullet level velocity how can you help me with this goal .also you all are great and i hope that each and every one of you have a great day today and your all so amazing thank you all
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mrfoo
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Mon Feb 12, 2024 3:04 pm

OK, you're young, and you're enthusiastic. I'm old, and cynical, and jaded. Here's some advice.

This is what's known as a "forum", and it's not even a particularly active one, even by 2024 standards. It's not instatwatbotik. There aren't 50 trillion twunts watching it for the latest news, poised ready to call you a cuck at a monent's notice. There's maybe a couple of hundred people watching this at best (including the three letter agencies), and you'll be lucky to get a response in a couple of days.

Ways you won't make friends:

Making multipl posts with identical titles
Resurrecting threads that have been inactive for decades with out-of-context requests
Running around shouting "look at me look at me look at me" and shitting in the corner behind the sofa

Consider yourself welcome, pull up a chair by the fire, relax a bit.
quinn whitsitt
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Tue Feb 13, 2024 11:42 am

thank you for responding and thanks for your advice your a great person but most of my posts are not about this subject but instead a thread in which pepole can come up with new ideas if you need any help or advice you can message me and i hope everyone on this form is going to have a good day
also is there anything i can do to help any one
Pennywise
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Tue Feb 13, 2024 12:02 pm

There is no way to use pressurized air as the energy source and not observe the pressure drop after use. An efficient system may be able to lessen the pressure loss, but it is impossible to eliminate it unless the pressure isn't what's being used as the primary propellant.

Many people have used pcp chambers for their sources.

The big thing to understand is that air pressure is relatively energy inefficient compared to combustible fuel sources (powders especially). If you are chasing the ft/lb of a smaller handgun with a sub .50" round, it's not impossible. However, if you're after rifle energy with a similar size projectile, you're in for a hard time.

A bullet is typically propelled by a pressure of several tens-of-thousands of psi as the powder ignites, and that heated pressure wave can travel much faster than ambient temperature pressurized air can. This means that even if you were able to achieve 20000psi of room-temp air behind a projectile, it can't match the velocity of a bullet with 20000psi of high temperature pressure pushing it. (Unless you use a lighter-than-air gas as propellant)

As hinted at above, I'd recommend you read through previous posts and learn what you can about the subject matter. There are MANY MANY posts which will teach you much about the dynamics of these devices.
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mrfoo
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Tue Feb 13, 2024 1:51 pm

OK, I'm gonna hit you again, perhaps less gently.

Quinn. What you are doing is not polite, and at best is creating cleanup work for the moderators.

Generally speaking, forums have their own rules, the ones for this one are found here, but there's a more general set of rules that are assumed to be general on most forums, this is basic netiquette. You should always read and understand the rules of a forum before posting. It is usually a very good idea to read a lot of messages before posting, to get a feel for the community. In the same way that you would hopefully do in real life if you find yourself in a group of people who know each other but don't know you. There's usually an introductions thread which you could avail yourself of, you'll probably find it in same forum as the rules thread.

In any case, this isn't social media. You shouldn't expect an instant, or indeed any, reply to any post you make, and you don't get bonus points for posting 50 questions, 40 of which are reworded duplicates, in 75 identically titled threads over a half hour period.

Post cleaned.
quinn whitsitt
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Wed Feb 14, 2024 8:54 am

Pennywise wrote:
Tue Feb 13, 2024 12:02 pm
There is no way to use pressurized air as the energy source and not observe the pressure drop after use. An efficient system may be able to lessen the pressure loss, but it is impossible to eliminate it unless the pressure isn't what's being used as the primary propellant.

Many people have used pcp chambers for their sources.

The big thing to understand is that air pressure is relatively energy inefficient compared to combustible fuel sources (powders especially). If you are chasing the ft/lb of a smaller handgun with a sub .50" round, it's not impossible. However, if you're after rifle energy with a similar size projectile, you're in for a hard time.

A bullet is typically propelled by a pressure of several tens-of-thousands of psi as the powder ignites, and that heated pressure wave can travel much faster than ambient temperature pressurized air can. This means that even if you were able to achieve 20000psi of room-temp air behind a projectile, it can't match the velocity of a bullet with 20psi of high temperature pressure pushing it. (Unless you use a lighter-than-air gas as propellant)

As hinted at above, I'd recommend you read through previous posts and learn what you can about the subject matter. There are MANY MANY posts which will teach you much about the dynamics of these devices.
its at 5000 psi 100 cu feet i found a tank for it and i have actual achieved self containg air canister by one way valve to achive it and i have actually made this work th main goal is to make sure other pepole come up with there own methods and mine dose use air pressure
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Wed Feb 14, 2024 1:20 pm

pennywise you are wrong i was able to build one this also is a suggestion area for pepole to talk to each other about there spudguns and how to make and improve there guns by learning from each other to improve are skills
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Wed Feb 14, 2024 1:23 pm

if any one whould like to know how to build this spudgun that is fully automatic and has adjustable power you may respond and i will tell you how but is there any suggestions you whould like to make
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Thu Feb 15, 2024 11:27 am

is any one there
quinn whitsitt
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Thu Feb 15, 2024 11:55 am

thank you mrfoo for cleaning the post
that was somwhat mean what you put on there
quinn whitsitt
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Thu Feb 15, 2024 11:55 am

is there anything i can do to help anyone
quinn whitsitt
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Thu Feb 15, 2024 11:56 am

hello
is anyone there
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