Harness the power of precision mixtures of pressurized flammable vapor. Safety first! These are advanced potato guns - not for the beginner.
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Ragnarok
- Captain
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Sun Oct 11, 2009 9:57 pm
Technician1002 wrote:They have some in 2 sizes. Neither of which is 42 lb.
The 42 lb. size is just the strict size of a "true" cannon. Other sizes should technically go by other names... but most people don't bother to differentiate. They are "cannons", but they are not "a cannon" in the strict sense.
Most of the time, I wouldn't give a damn about differentiating the sizes. But if Moonbogg is going to consume other people's time by using definitions so obscure that only he uses them, then I'll start being "petty".
Does that thing kinda look like a big cat to you?
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D_Hall
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Sun Oct 11, 2009 10:15 pm
spudkilla224 wrote:And last off when i'm using hggdt program it comes up with an answer that says "Combustion Incomplete" what does this mean but then it says underneath of it " No Errors".
"Combustion incomplete" and "No errors" are two unrelated messages.
"Combustion incomplete" means that fuel is still burning at the time the projectile leaves the barrel. At the very least this means your gun will perform better with a burst disc that goes at a higher pressure.
"No errors" means just that: no errors. It doesn't mean that the sim is perfectly accurate or anything, it just means taht it didn't encounter any glaring problems in the scenario (It's OK to still have gases burning...Doesn't make for an optimal gun, but the laws of physics won't be offended or anything.).
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Moonbogg
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Mon Oct 12, 2009 9:21 am
The 1.5" x 12" seems slightly long to me at least. I would want 2 spark gaps in there to rain on DDT's parade as much as possible, but thats just my own gut feeling.
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Moonbogg
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Mon Oct 12, 2009 12:14 pm
spudkilla224 wrote:yeah so would 10" lenght be ok?
Well I can't say what length will DDT because I don't know. All I can do is share what I would do. If it were me I would use HGDT to eliminate unnecessary pipe length. In HGDT, reduce the length of pipe by an inch at a time and see how much performance is lost. There should be a sort of optimum length depending on your barrel. Using a longer length will only provide a small increase in performance and will only add extra weight and increased risk of DDT. I would start at 6" in HGDT and see how the performance curve goes from there. Also, DDT can occure in the barrel itself, so make sure you use a burst disc that can let that combustion build up quit a bit inside the chamber itself.
