Pcps are more efficient for me as I don’t have to use any muscle power. The tuxing compressor does it for me.
Air is readily available if you have your own compressor just like with a springer.
But it does mean that for a spring gun the barrel length required to extract all the energy from the air pulse is much shorter.
A 12ftlb springer only requires about 10" barrel for .22 and 13" for .177. Rammers slightly shorter than that. PCPs about double that.
Many airguns have a barrel that isn't the optimum length for efficiency because other factors such as excessive overall length, excessive forend weight, cocking leverage or even cosmetics also influence the design.
.
Pcps are more efficient for me as I don’t have to use any muscle power. The tuxing compressor does it for me.
Air is readily available if you have your own compressor just like with a springer.
65.3cc's by my maths ,
As I said above, in a PCP the energy that you have put in to the springers spring when you compress it cocking the rifle for each shot, does not exist so that stored effort/energy has to come from extra compressed air.
For a given pellet in a given bore & barrel length, the energy (from the compressed air) required to reach a specified muzzle velocity will be exactly the same ( vol A), so the shot is equally efficient.
BUT to replace the energy from the spring you need another 150%ish of vol A (vol B).
All vol B does is push vol A in to the breach it then exits the muzzle as wasted air once vol A has shot the pellet out.
In a gas ram vol B is contained inside the ram, but You again have to impart the energy in to the gas by physically cocking the rifle to compress the gas for each shot.
Check your maths
Volume of a cylinder = π x R² x L
3.1416 x 1.3² x 8 = 42.27 cc
That's mine.
I think there's an assumption that air is like a liquid and that the pellet is pushed all the way down the barrel by a consistent volume. That's not the case and it's a highly complex system to do with pressure waves and flow, which aren't the same things.
I agree the comparison with springers and other plants is flawed because of the stored energy of the power plant (Spring/Ram)
Yep, You beat me to my correction confusing my circumference of a circle, with my surface area of a circle.
silly old bear