Snowpeak P35X fpe limitations

I recently purchased a P35X in .177, primarily because of the added 65 cc plenum and the longer barrel. I purchased it from mundilar in Portugal so no power limitations.


However, I can’t get it to shoot faster than 860 fps with JSB Exact Heavy 10.34 grains even with the hammer spring fully adjusted.


I’ve also tested:


  • JSB Beast 16.20 gr = max 720 fps.
  • JSB Monster 13.43 gr max 776 fps.
  • JSB KnockOut Slugs in both 10.03 gr and 13.43 gr max fps = even less then the two pellets mentioned above.



  • I expected it to have around 29 fpe with the jsb beast 16.20 according to others reviews, but I'm close to half of that fpe, 18, 65 fpe / 720 fps when shooting the jsb beast. 16.20.


Has anyone experienced similar performance limitations – and found a solution?

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