Fire_at_will
25gr i shoot 960-970fps, extreme accuracy but results will vary.
As for the valve adjuster, i never use it. I just remove it completely. I call bullpoop on the people who say you need it for "harmonic tuning", load of crap.
That’s a very bold statement. Let me explain why I feel it is also a very ignorant statement (calm down… I said ignorant, not stupid… there’s a big difference).
I think you're missing the point of the valve adjuster. I understood the primary purpose of the valve adjuster to be a tool for air efficiency. The VSA's primary purpose is to time the closing of the valve to just before the pellet leaves the end of the barrel, so there is no wasted air released after the pellet is no longer using that air for propulsion. If the valve is still releasing air after the pellet leaves the barrel, you're just blowing air out the barrel, and needlessly reducing your onboard air supply.
Because the VSA does change the velocity of the pellet once it is in the effective range of adjustment, it most certainly does have a secondary effect on harmonic tuning of the airgun. To offer a really simplified illustration/explanation, in a perfect world of no movement when holding on your POA, your barrel is still, lined up on your POA. When the airgun fires, harmonic vibrations travel through the gun and barrel, and the barrel oscillates around the POA it was holding. For a simple illustration, let's say the barrel just oscillates up and down. As it oscillates up and down, it will swing up to its highest point (moving away from the POA on the high side, causing wider groups if the projectile exits here). It will then swing back down, passing through the mid-point of the oscillation (where it is back on the POA, causing tighter groups if the projectile exits here), continuing down to the lowest point of the oscillation (again moving away from the POA on the low side, causing wider groups if the projectile exits here). "Harmonic tuning" for accuracy is all about timing the projectile to exit the barrel while it is oscillating up or down as close as possible to that center point of the of the oscillation, where it is back on the POA. We control that timing by adjusting the projectile velocity through the barrel, speeding it up or slowing it down to time its exit from the barrel at the sweet-spot of that gun's harmonic vibration oscillations. This could require an incredibly small change in velocity, and this is where the VSA comes in... it provides much finer control over the projectile velocity than an adjustment in regulator pressure or hammer spring tension (which can also significantly change the oscillation, so now you're trying to hit a moving target).
Keep in mind, changing the regulator pressure and the hammer spring tension will more significantly change the harmonic vibrations of firing the airgun. One could think of it as adjusting regulator pressure and HST will set the harmonic vibrations, and can be a coarse adjustment, then the VSA will allow you fine adjustment to “tune” to those vibrations/oscillations.
If this explanation is giving a reasonable picture of what is going on, you should then be able to understand that a more accurate explanation of harmonic tuning doesn't require that the projectile exit the barrel while oscillating past its original POA, but rather that it just exit the barrel at as close to the same point in the given oscillation every time. This will give the tightest groups, even if POA and POI do not match.
If my above stated understanding of the harmonic tuning process is bullpoop, and using the VSA in this process is a load of crap, please offer and explanation of why, supported by the physics of firing an FX Impact, because if you are correct, I am the ignorant one, and have a LOT to learn that I thought I understood.
