Just got a P17

[Insanity]

I think this winter I will massage mine to get some more fps.

My P17 shoots a little hotter than my HW40, but it also has a little more "bark" to it.  I think that will be the result if you "massage...to get more fps".

Both of my P17's average 446-447fps with JSB 7.33's after a gentle "massage."  I have several preps I do to a P17 when I get it, but the one that really bumps up the fps is getting the compression just right.  It has to be very close to zero dead-space, but not quite.  One of them was only shooting 395fps, so after experimenting with aluminium tape on the piston (6 layers or 0.03") I ended up gluing a 1/32" thick, ~24.5mm wide aluminum disc to the face of piston.  I got it from a craft store.  The other gun arrived shooting 425fps, so all it needed was 2 layers of foil tape to have full compression.  There is about 7-8fps hiding in the transfer port as well - it can be slightly enlarged (my guns stopped gaining after .116"), and the part where is meets the valve can be rounded off a bit if you can figure out how to get in there...

I will be playing around with aluminium tape and port size. I thought about bringing the tap just past the intake then relieving the tape for the intake port but that may just be snake oil.

[Tom Tucker]

I tried making a relief for the port, but it didn't seem to make any difference...