Thousands of PSI?

Not trying to be argumentative but somehow I can't see a springer reaching anywhere near that unless I am missing something in the physics. For example a .22 benjamin using CO2 claims "up to 430 fps" that is with CO2 which has a vapor pressure of 970 PSI @ 80 deg F.

Just for amusment I ran the spring wire diameter, free length, OD through a spring rate calculator and at full compression it has 128 lbf(pound-force)of force or a rate of 34.1 lbf/in., since the spring is not 100% compressed the spring force is probably in the 100 pound range.

Now there is also adiabatic heating of the air as it's compressed which will make the air more dense, for instance at atmoshpheric pressure 0PSIG it's like .075lb/cu ft heat it up to 300 deg at 100 psig and it .408lb/cu ft. No idea how this interacts but it does explain dieseling with the heated air.

I like the analogy of the hammer and it does make sense for piston weight to have enough inertia to follow through as the spring force weakens the further through the firing cycle things move.

Following along the same lines I wonder if a large releif port in the first 1/4" of piston travel would not assist in accelerating the piston before it hits the wall of air to compress. Similar to a brake master cylinder with the releif port. Something like that could probably even be incorporated in the transfer port with crossdrilling and a hardened ball & brass valve seat but the simplest would just be a hole in the cylinder that the seal passes.

I am not trying to re-invent the wheel here just tossing out some ideas and thoughts.

Kristin

PS- After the sun was setting in the west I thought of a couple more tests (gee I love messing around with experiments) I fired up the compressor that tops out at 120 PSIG, loaded a pellet into the spare barrel and using a blow gun with a brass tip popped a few into my foam block, average penetration 1.5-2" almost the same as my pre-cleaning experiment.

Next I got a piece of leather, soaked it in water and sat it on a bit of wood, pressing the muzzle down fired the gun a few times w/o a pellet. Well it didn't blow a hole in the leather, barely marked it more than the pressure of me holding it to the floor and after a second or so when I released I could hear a hiss of escaping pressure.

So my conclusions about this point is the cylinder pressure is somewhere in the 100-200 PSI range, I may try tomorrow to get a better seal to the breach end and try again as I suspect there may have been some leakage as I was juggling the barrel & blow gun in the fading light. Begining to think it's more about the volume of air moved than the actual pressure and delivering that cleanly to the skirt of the pellet.