Tuning Low fps the first 10 shots FX impact mk2 compact.25

My two RAW's took 1 shot for the regulator to recover after sitting overnight. Changed the regulator's seat to peek and now every shot consistent no matter how long they sit.View attachment 271939
Mine might have variation first shot as well - don't care. The HM1000x is so dead-nuts accurate that even when I fail to close the cocking handle completely and there is a quick blast of air as the pellet goes thru the barrel, it still goes into same group or center x on target! They are probably the least complicated and most accurate "mass produced" air rifles there are. Don't know anything about Thomas, so there is that.
 
My .30 M3 running 92fpe takes 3 shots to be close and 4 shots to be 100% velocity after sitting 12 hours.

My .22 M3 running 41fpe takes 8 shots to be close and 10 shots to be 100% velocity after sitting 12 hours.

Both of these are ~95% tunes, neither guns have hammer springs/weights. 3-4 shots I can work with, although I'm not thrilled. 8-10 is a bit much. I suspect people maxing out their M3s, and especially the ones running hammer weights/spacers, aren't affected by this much, so that means there is little to no complaining about this from a portion of the user base.

I think the research done by @mubhaur and other forum members have essentially settled the cause of this, and it is probably the single biggest flaw in the Impact. Is FX going to offer a fix?

One question I have for people with Mavericks and Wildcats - How do they do in this regard? Since their valve system is much simpler and lacks these additional o-rings unique to the Impact, I would expect them to be much more consistent after sitting.
 
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Mavericks and other more basic PCP’s only have two things to worry about. Number one is reg creep. Number two is axle grease or something else causing the hammer to have inconsistent strikes. Impact owners have that wonderful valve knob. But it comes at a price. All this chatter, though most new M3 owners seem to be oblivious to it, probably isn’t going unnoticed. It will be addressed with the M4 along with the barrel and the guns anemic spine.
 
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Very first time - about a year ago - I did some machining on the Rear Block also Valve House and Peek puppet.
Ones there I did polish the tungsten Valve Rod to mirror finish. If you have a closer look the rod is not grind but coming from a lathe.
The original PUR90 is still there since I got the Impact in Feb.2020 and over 16K shots on the .25 Impact (I stop counting).
I don't have the phenomena you describing but I am playing my game with a powercurve between 100-120 Joules (74-93 FPE).
 
Did some tests on the old valve rod, after I polished it mirror finish, the old pur90 ring does not stick but the brand new one does. Maybe it needs to be used for a while to break in? Talked to fx about it and they said I had regcreep, but I said that the o-ring stuck to the valve stem, they advised to polish it and oil it. Would then make sure I did not have regcreep.They did not recommend a nbr90 o-ring, told them that it works without problems with that o-ring but not with a pur90. Im gonna leave the gun as it for no and see how long it works.
 
Yes it was tested it still sticks you can adjust the hammer just a tad to help over come it on first shot which seems to be the worst unless your shooting 100 yards or more a 20 fps you won't really notice a unregulated gun tune within 20 fps curve is actually pretty good tune I dry fire my first shot before I go out hunting on my mk2 impact I'm waiting for the larger plenum 720 for my mk2 to show up and am doing a peek washer with a viton o-ring