AA/CZ T200 PCP Rifle - Chrony Results: Explanations Please?

[Aimstraight]

Mystery now solved - F1 Chrony string readouts are displayed in reverse order!

I ran the AA/CZ T200 rifle over the F1 Chrony (.177, 12 ft.lb rifle) using lubricated Superdome pellets and have some unexpected results. It has an AA Ten Shot Conversion fitted, so the shots were done fairly quickly in groups of ten shot strings. The cylinder was initially charged to 170 bar (that is the limit for the gauge fitted on the cylinder), the cylinder is non regulated, so I was expecting a power curve, what I did not expect was a power saw tooth? For the first 30 shots the velocity and power was fairly steady, then from shots 40 onward instead of a gradual reduction in velocity and power, there is a saw tooth effect? The velocity/power starts low then ramps up, repeating this cycle when the magazine is changed. Anyone have an idea of what is going on, maybe something to do with dynamics of the valve, hammer spring, cylinder temperature changes in between changes of the magazines? I appreciate a regulator could be the solution to even power/velocity, but I would first like to understand what is going on with the ten shot conversion/ten shot string situation.

Thanks in advance.