For a modern magnum spring piston rifle there are a lot of factors that can vary the peak pressures and temperatures. I think you will find peak pressures can spike into the 2000-4000 psi range and temperatures can spike into the 2000 degree F range. The temperature spike duration is very short (maybe 100 -200 microseconds?) and the thermal mass of that air volume is small so synthetic seals are not damaged by the brief exposure.
Peak temperatures and pressures occur during pellet travel in the bore and are significantlyhigher than the corresponding values at bounce time. The highest chamber pressure andtemperature are 29,248 kPa and 1452 K, respectively, while the highest values for thebreech are 27,298 kPa and 1,506 K.
Seems to me this is one of the situations where measuring the temperature will alter the results.... eg. using a wire that melts, or a temperature probe that heats up, etc.etc.... Anything that works will by definition be altering (lowering) the actual temperature spike.... The result would have to be worded " the temperature exceeded XXXX *F ".... It sound like Travis might be trying to utilize Adiabatic compression to increase power output in some way.... I'm sure he must realize that Adiabatic compression works both ways, and if you use that energy spike to heat a larger volume of air, or turn it into Kinetic energy, you will lower the spike temperature and pressure.... Perhaps he is thinking of using a PCP to accelerate a piston, which will then fire the pellet from the compressed air.... hoping for boost in power?.... My gut tells me that inserting another step in the process will reduce efficiency, rather than increase it.... but I could be way off on what he might be working on.... Bob
Perhaps he is thinking of using a PCP to accelerate a piston, which will then fire the pellet from the compressed airBob
On a typical gas ram or magnum break barrel does anyone know the heat it produced on its firing cycle and pressure?
Miles.... Yes, but don't they use a light gas to drive the projectile?.... and a burning propellant to drive the piston to compress said gas?.... I was not aware of any using compressed air to drive the piston (ie a PCP).... Phillip.... I would suggest that is then no longer an airgun.... at least not by your Federal definition of one....Bob
Definition of a Firearm according to the ATF:18 U.S.C., § 921(a)(3)The term “Firearm” means:1. Any weapon (including a starter gun) which will or is designed to or may readily be converted to expel a projectile by the action of an explosive;