-
If you enjoy the forum please consider supporting it by signing up for a NES Membership The benefits pay for the membership many times over.
-
Be sure to enter the NES/MFS May Giveaway ***Canik METE SFX***
homemade 25mm pneumatic sniper rifle
- Thread starter benster
- Start date
![[smile]](/xen/styles/default/xenforo/smilies.vb/001.gif "Smile [smile]")
N.E. CHARTERS
Banned
- Joined
- Dec 7, 2005
- Messages
- 1,328
- Likes
- 49
Fun Fact: PVC shards can't be picked up by X-Rays
PVC? They are out of their MINDS!
It can and will explode. Just a matter of time.
Whats that boy been drinking?
PVC? They are out of their MINDS!
It can and will explode. Just a matter of time.
Whats that boy been drinking?
Don't know much about PVC huh?
He is using pressure rated PVC pipe and says it many many times. Not the DWV crap for drainage.
schedule 40 PVC pipe in the 2" size is rated to 280 psi working pressure. (Non Shock, water pressure) Which would lead me to beleive that reflects a minimum factor of safety of 2X (if not more) which is ~560psi. and that is for the "pressure tank" which wil not see a shock load.
the barrel assembly which will see the shock load is rated to 450 psi.
considering they are most likely filling the tank to ~120psi max with a standard air compressor (probably mopre like 80) they will be fine.
Chris
NES Member
- Joined
- May 24, 2005
- Messages
- 13,411
- Likes
- 8,254
Needs rifling, notice the tumbling on the entry hole. (^_^) Or at least a better balanced projectile.
I did see him note that "PVC shards don't show up on x-ray". Something tells me an early prototype had a catastrophic failure. Hence the recommendation for safety glasses.
I did see him note that "PVC shards don't show up on x-ray". Something tells me an early prototype had a catastrophic failure. Hence the recommendation for safety glasses.
N.E. CHARTERS
Banned
- Joined
- Dec 7, 2005
- Messages
- 1,328
- Likes
- 49
Paint a Pascal Picture
Don't know much about PVC, Dont know much Biology, Dont know much about the French I took.
But I do know Boyles Law which states
Boyle's law states that the volume of a gas is inversely proportional to the pressure applied to it. In other words, the pressure of a gas times its volume is a constant. It is not necessary to know the exact value of this constant to meaningfully understand the behavior of gases. The law was discovered by Robert Boyle in 1662. The standard measurements for volume and pressure are cubic meters and pascals (or atmospheres
Boyle's law is a basic law in chemistry describing the behavior of an ideal gas under a constant temperature. An ideal gas is a perfectly pure gas undergoing perfect elastic collisions with its container
The modulus of elasticity of PVC is pretty high IE: It will stretch like Gumby.
Plastic tubing is made from four basic materials: PVC, polyethylene, nylon, and PTFE. PVC can be used for pneumatic lines at pressures to 125 psi with continuous temperatures to 100°F.
It would be interesting to put a transducer on the PVC Gun and measure what the pressure of the barral is upon execution of the valve.
Don't know much about PVC, Dont know much Biology, Dont know much about the French I took.
But I do know Boyles Law which states
Boyle's law states that the volume of a gas is inversely proportional to the pressure applied to it. In other words, the pressure of a gas times its volume is a constant. It is not necessary to know the exact value of this constant to meaningfully understand the behavior of gases. The law was discovered by Robert Boyle in 1662. The standard measurements for volume and pressure are cubic meters and pascals (or atmospheres
Boyle's law is a basic law in chemistry describing the behavior of an ideal gas under a constant temperature. An ideal gas is a perfectly pure gas undergoing perfect elastic collisions with its container
The modulus of elasticity of PVC is pretty high IE: It will stretch like Gumby.
Plastic tubing is made from four basic materials: PVC, polyethylene, nylon, and PTFE. PVC can be used for pneumatic lines at pressures to 125 psi with continuous temperatures to 100°F.
It would be interesting to put a transducer on the PVC Gun and measure what the pressure of the barral is upon execution of the valve.
I took chemistry too. PV = PV.
should we also discuss Charles' law or Gay-Lussac's law. or maybe the combined gas law. as temperature is also very important.
also PVC has a LOW Modulus of elasticity. which means it will yield quite a bit for a fairly low stress. or stretch like gumby as you mentioned.
the pressure of the barrel will in all circumstances be lower than the pressure of pressurized reservoir.
