I don't think you need to worry about the 0.005" tolerance of the BBs. You need to worry about the tolerance of the internal diameter of the 5/8" conduit. I wouldn't think conduit is all that precise. Is the conduit metal or plastic? Is the conduit welded? If it is welded, it'll have a slight ridge ...

For your second question this is where you use the ideal gas law; PV=nRT where P=pressure, V=volume, n=number of moles of gas, R=gas constant and T=absolute temperature. You want to calculate the final pressure so rearrange the eq to; P=nRT/V For n you'll need to know the weight of the gas and its m...

Use a 555 timer to control a stun gun. IIRC, stun guns spark twice per second or so. Use the 555 in an astable mode so it triggers the stun gun once every few seconds. Fairly easy to adjust both the on time of the stun gun and the time between firings. Check Latke's page. I believe he has a 555 base...

People aren't being very accurate. Stainless steel will rust. It is much more resistant to rust than is iron but it does still rust. Aluminum actually "rusts" faster than iron. But aluminum oxide forms a protective coating which protects the aluminum underneath from oxidation. Iron oxide flakes off ...

you do know that the difference between 450 and 650 fps is about the speed that a good pitcher can throw baseball (which weighs more than a tater) with his arm dont you? it really isnt a whole lot if you think about it. and also think about it, if it is 30 degrees out side, then the proformance wil...

Why do you want a single spark? Multiple sparks don't cause any harm (they also don't really help anything).

Yes, a gun fired with Helium will give a higher pitched bang. An instrument played with a breath of Helium will also be higher pitched. (How much higher depends on the details of the instrument and how big a "breath" is. Almost no affect on the pitch of a flute. Big affect on the pitch of a trumpet ...

pyromaniac wrote:what psi will a mini generate.

First approximation... exactly the same as full size gun.

Second approximation... slightly less than a full sized gun.

the muzzle loaders actually didnt use spheres... those were muskets, my friends dad has a muzzleloader that is rifeled, and i have one of the bullets, it looks like a very stubby .50 cal round which in fact it is :roll: :wink: A musket can be either smooth bore or rifled. (Wiki says they converted ...

What kind of sparker are you asking about, flint or piezo? Piezo sparkers never "run out", though sometimes the hammer mechanism fails with use and the piezo quits working. The piezo electric crystal itself will never "run out". Flint sparkers wear out the small piece of flint. You can buy replaceme...

GGDT will calculate the optimum C:B for a particular chamber and valve. Usually the optimal C:B is around 0.25 or so (a compressed air gun will be most efficient with a barrel ~3x longer than for a similar sized combustion gun). But, efficiency is not a real important factor in a compressed air gun,...

Actually, Latke's CB tests only pertain to taters and his custom gasket slug, and his choice of chamber diameter and volume, barrel diameter, fuel, number of spark gaps, ...

Yes, there is a lot more testing to do. Heck, Latke's data is just about the only reliable data available on combustion guns.

Benstein: Yes, I know hybrids don't respond to friction the same way a standard combustion does. The point is that friction is different between a spud and a golfball. The optimal CB for a hybrid firing a spud is not necisarily the same as for a golfball (which has much lower friction). With a spud ...

There is something seriously wrong with the schematic. As drawn, it won't do anything except discharge the battery. The neon lamp will never light, the caps will only get charged to about 1.4V. The 9V battery would be totally dead by the time C1 actually got to 1.4V. A neon bulb requires at least ~7...

Didn't boilingleadbath post a week or so ago about a much easier way to get to C:B data without going through the slow process of chopping the barrel? I though his approach (if it was his) was a reasonable way to get the entire C:B profile from a single shot of the gun. Not only saves having to chop...