[Korea Has Nukes]

So I've been playing around with piston weights. I have purchased enough lead tape to be on a golfing watch list. I currently have been testing on two pistons. Springer custom works and novritch ssg10. I've doubled the weight of the scw but I cannot add anymore than that because of the design. It's not a good piston to add weight too. The novritch though is excellent for lead tape. Letting me almost triple the weight.
The barrels I've used are a 430mm aa, 490esc, 300 aa, 370maple leaf. My Chrono is accurate. Starting off with a rapax 4j spring I've currently been playing with in my ssg10. With extra weight both pistons see a slight -20 fps with .48 bb. From 430>410 on the first barrel. Second spring was a pdi 520. Very similar results this time as well. I understand heavier pistons can make short barrels better for sites that still Chrono with .2. But is there anything regarding high fps springs like I'm using? My theory was the heavier pistons would be better with longer barrels to continue pushing air behind the bb. But right now I'm only feeling a harder recoil and accuracy seems worse. ..

 

[Blind Sniper]

I’m curious to know what your outputs are between a .48 and a .20 for the different combinations. All with the hop set for the .48. I did a bunch of testing before and didn’t have any creep that was THAT impressive with a long piston like that. Then I started to believe joule creep was heavily exaggerated and just enjoyed the fps boost of a shorter (EdGi) piston.

 

[Masada]

I've done a bunch of messing around with different piston weights as well, but it's hard to come to a general guide on using them.

I'd recommend adjusting your hopup for the particular bb weight you are shooting with for each test. I know it's pretty time consuming, but it should provide a better idea of what's going on. For example, if I was to set a gun up to shoot 3.6J with a 0.66g and then chrono with a 0.48g without adjusting the hop it might show a 1J reduction in output, but if I was to readjust for the 0.48g it might gain back most of that original energy lost. Just an example, it definitely doesn't always work like this.

Spring design, spring preload, cylinder volume (cylinder head length if we are just talking about VSRs), nozzle inner diameter, and barrel length (and inner diameter to a lesser degree) all factor in to this as well. Good luck.

 

[1tonne]

Pistons that take 11mm springs are better for joule creep over pistons that take 13mm springs as they can fit more weight on.

Here are some results I got about 5 years ago. I can't remember what the spring was but I am pretty sure it would have been a Laylax SP190.