"maxony"
I wish I took all of the measurements while it was apart. The seat diameter is a little over 5 mm. That is where I got 30 lb air pressure when closed. The air path around the poppet body is much larger than other much more restrictive air passages
I don't understand the term "easier to unseat". Original poppet looks to have a nylon seal. It should not be sticky.
Well I'm not certain of the Rockwell numbers on the Delrin or whatever the substance is that the original seals are made of, and I'm not making predictions based on theories (got a guy on another airgun site who likes to do that and get in arguments with those who have the actual items for testing) I'm using my first hand results with my QB. I filed down my original QB poppet at both the head and a section on the stem to allow more flow thru the throat of the valve. I then was able to get some delrin and make my own poppet head. When I put my delrin poppet head on the original stem (which was modified) I gained 30fps with NO OTHER MODIFICATIONS TO THE GUN.
I can tell you, from actual experience, that the seal on the QB poppet is positively softer then the delrin one I made. This softness allows the poppet seal to compress more. When the stem is struck the force has to first "un-compress" the seal, and then unseat it to allow air to flow thru. It positively takes more force to do this. Since more of the available force is used to "un-seat" the valve, less force is available to contribute to the dwell of the valve, hence the valve will not open as far nor as long. This results in less FPS with the other parameters being the same.
Think about jacking up a car. Put the jack under the frame of the car and see how long it takes to get the tire off the ground. Now up the jack under the lower control arm and see how long it takes to get the tire off the ground. Without having to first overcome the coil springs (or torsion bars) the jack gets the tire off much quicker doesn't it? Is it still the same result? I don't think so, and here's why. The jack can get the tire the same height without traveling as far, right? If the jack does travel as far (using the same amount of effort) then the car is raised much higher, right? So you can lower the jacks "effort" and get the same result, or you can use the same "effort" and it will raise further. Same with the valve, but hopefully easier for everyone to understand. You can lower the hammer spring force and get the results or use the same hammer spring force (as I did) and get more "raise", 30fps in my case.
Sure that .01lbs of force(if that # is correct) might not seem like a big difference, but having the valve open just the tiniest bit further, or longer definitely has a difference.
Case in point being my Compatto. With the slingshot hammer adjusted perfectly I get 25-27 shots starting around 910, peaking at 938 and back to 910 over a 3400psi fill. If I turn the adjusting screw (which is an M5 I believe) just 1/4 turn in, the velocity will start at 910 and go down with each shot. This is with just 1/4 of a turn. If this is a M5 x.5 screw then that's a length of just 1/4 of .5mm or .125mm which is just 0.00492126 inches. How could that small a length make such a difference? I'm not sure, but it does.