Yes, it's always advised to check the power output periodically anyway for "health check" and legality reasons. Also nice to see the power rise as a springer breaks in.

However, the thread is concerned more with whether the output varies as the mechanicals warm up, mainly through repeated rapid use but also (and this has a much bigger influence on output) on the output in different ambient temperatures.. Before Jim's enlightening work, many might argue that the springer's power was reduced in colder conditions due to the viscosity increase of any lubricating grease. His work has proved the opposite. A lot depends, of course, on the individual gun's set up, especially the piston seal fit.

I seem to remember that gas rams behave pretty much the same as springers.

PCP power output drops as the ambient temperature drops. Better to acclimatise fully when charging etc. But they're inferior to springers anyway! (@Steyr - ).

And the poor old CO2 powered guns definitely suffer when those temps drop.