PeteS wrote:
Due to temperature change? Or do you mean too quickly for the check valve to pass the pressure to the measuring chamber? Something else?

Temperature. My hybrid will actually pull down to a substantial vacuum after the piston valve closes from the cooling effects.

Potential issue: is your gun running enough pressure to successfully deform your projectile to fit the rifling? (I doubt the average n00b's does, depending)

Are those getting sabots?

I assume those were not the saboted projectiles?

I think I'm going to have to get me a shotgun soon. Her in 'murica, that's just a short drive down the road.

Eh, I don't think there's any flame war going to happen. Not here, anyway - we're pretty civil about this. :) And yes. Like I said, there's no such thing as sex with a feminist. :) Also, I know of zero female here to argue with his view. Much feminists, who are obviously too refined and feminine fo...

Post-it is the brand-name that 3M wants us to promote. We don't use post-its much, but they do give us shit-tons of electrical tape, sandpaper, and epoxy (maybe 10 gallons). I will say that the stuff that comes in these syringes is amazing. There is a caulk gun type dispenser for them and is mixed i...

We have a ~9.7kw axial flux hub motor. The car weighs approximately 500 lbs. I do not have acceleration data at this time, but we do have quite a few safety regulations. Full roll cage, 6 point harness, fully redundant braking system, crumple zones, crash safety from all sides, ability to get out in...

They are heavier and more expensive per kWH ($4343/kWH), but cheaper per KW peak ($48/kW). That hobby pack is also presumably very marked up. A typical electric car cruising uses about 15-30KW, so an hour commute would use 15-30 KWH. Add another 2KW if you use the heater or AC. Cells are about $600...

LiFePO4 batteries are actually pretty good about cycles. The ones we use on our solar car are rated to 2000 cycles with, I beleive, 90%+ capacity remaining. That's about 3 years at 1 full discharge per year, which you will not see on average days. The cells were about $600/KWH, and peak output of ab...

Interesting. I wonder if the NSA has secretly subpoenaed PCGuy yet.

Is there any legal obligation to get classification? Or is it just insurance that they won't later prosecute you for having a 'destructive device' (and manufacturing without license, tax evasion on the tax stamp, etc)?

(assuming US)

Grizzley, Harbor Freight, Craigs List, local industrial surplus. Hell, I think you can buy a mill on amazon with prime shipping.

It might. If the door is not deadbolted, you can use a credit card to shim it open (if it opens inward, doing this from the outside is easiest). You can then take apart the lock. Alternatively, turning the key around and around swill usually resolve it (don't break off the key). If you can't get the...

If you really want to shut them up, post a graph of your biweekly paycheck somewhere in the work area. Not sure that's worth the loss of privacy to you, but it might gain you some respect.

Most definitely, up to a point... As you approach the speed of sound, pneumatics sort of reach their limit of muzzle velocity (although there are some cases where a pneumatic may have exceeded the speed of sound).

I would recommend downloadingGGDTand playing around with it.

the same amount of chemical energy, but there is also 'mechanical' energy in the compressed gas. This is the amount of energy that would be released if you simply opened the valve. ie, a if your cannon was a pneumatic with 9 bar of gauge pressure in the chamber.