does anybody know how to keep a marble in the barrel. i have a problem with the marble falling out while i'm about to shoot. does anyone know any ideas for a normal marble (not a metal baring using a magnet)

can anyone give me a link or something on how to make a homemade shock pump?

using a homemade or a bought?

why do some say they are going to go 300 psi and they cost 30-40$ and some say they go to 400 and cost $20

whats a shock pump

What kind of pump can i get that gets me up to over 100 psi? Is there any? I know i can do it via compressor and co2 but how obout portable? 120-150 doesn't count.

If i get 2 pieces of copper pipe and put a s h i t load of solder properly to the joints, how much psi can it hold? maximum

um i don't quite understand the entire thing, besides drilling holes makes almost no difference.

fps, um i would say it is possible, but you would need the exact portion of water and gelatine every time. And you would have to do some experimenting with a chronograph to figure how many fps is per inch of penetration. Good idea though.

Would schedule 40 cast iron be good enough for about 500 psi (co2)? or do i need schedule 80 cast iron?

if i would dump the pressure into a 1/2 inch dia chamber 6 inch long, what would the pressure be in the chamber?

um yea, thats a good idea for a cheap glue gun, but a good gun should head up in about 2 minutes.

Wouldn't the tip cool down after a minute?

i agree with hi, but weight to shift over it would have to be a throw of at least 15 feet.

The only way i see it is shooting it from something

So in one temperature, is the pressure in the tanks exactly the same?