Thanks that makes for a good read with some interesting points.
I've been shooting mine today and it doesn't seem to be particularly hold sensitive, no POI movement between stances and it can shot off of the floor (HFT prone position). I have only been shooting at 27y but thus far it shoots ok. However in my opinion I could do with an additional 20-25fps.
I'm going to put some more pellets through it to about the 750 pellet mark and then re-chrono. I have emailed Steve Pope with my findings. In theory it would add up that the piston seal is too tight within the compression chamber as the washers make no difference to the muzzle velocity.
Just out of curiosity what lubricant are you using around the piston seal, I've only dabbed the tiniest amount of Molly grease around the outside edge of the seal.
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