My regards to all members ! May i have to post something many many months but i am always here daily ,reading every interesting thread and enjoying our lovely forum.
There is a well known problem with the first gen impacts that can not fit inside the action the power plenum or the later 720 plenum .
I mean if you will try to upgrade it with any type of fx pp older or latest you will find a serious difference. Is going so tight inside the action clamp that you destroy always the 2 orings ( I think 9x1.50 , 90 hardness) .
In my case I followed the instructions of a well known airgun store of Spain which I have seen in YouTube.
Long time ago I recommend as well in one of my posts, the same method to some members who have the same problem .( now I regret for this and I apologise).
According the instructions of this store you remove the screw from the action clamp and you insert it and start screwing it from the opposite side by using the same time a metal round between to open the clamp ( I don't know how to describe the metal round in English language but probably you got me what I mean) .
I tried very carefully by turning 1/4 each time and same moment trying to insert the plenum inside without damaging the orings .
When I assembled the gun ,it was leaking instantly the air near the power wheel.
After many many attempts assembling and disassembling the leak remaining the same.
In the end I used a microscope I have for barrel inspection and I see inside the clamp a small line like a hair .
Suddenly I realised that outside of the action the crack was more visible . It was a crack in action .
That was the end . Oufff!!!!
I assume that aluminium material has very tight tolerance and is not elastic at all and I have the feeling that even if I was going carefully step by step in the end I passed the limits .
I leave and working outside far of my country and I have the change to enjoy my airguns once or twice per year in my vacations .
And now I was 2 weeks for Easter vacations ..
Without any second thought I called the official Fx importer of my country ( Greece) and I order one new action .
I was looking it in his website long time that was available one piece and was brand New for impact x .( same is mine) .
I started searching in airgun nation to confirm that this block it can receive the latest regulator bodies 10 mm and not the first gen 8mm.
When the vendor confirm that is writting on the action impact x I order it imediately .
I want to mention that his price on the site was 280 euros and he send it to me on north Greece for 250 euros including the transportation fee when the same time in other stores in Europe the price is 480 for the impact action older or newest .
Next day the new action was in my home .
The funny think ?
Saturday Easter night after 12.00 midnight I am starting to assembling the gun .
There is a storm in area and electricity suddenly is cutt off in all town.
I switch on few candles in the table and wearimg a head light .
I have disassemble honestly maybe more than hundred times this gun ( specially the first 2 years )but never I enter so deep in action like safelty small spring and metal balls .
After 2 hours working almost in the dark
Gun is ready and keeping air perfect .
I installed as well the new 720 pp and the new type hammer spring holder ( the shorter one 16mm,before I have the 18mm ) and newest hammer spring adjuster .
I want to mention here that my gun is full modified from day one back in 2019.
Polish power plenum , valve seat open 7.6 mm ,valve house tp to 7.6 mm , rear block tp 7.6 mm ,huma air brass double transfer port , pin probe handmade in lathe ,hammer spring from huma 57 cm ,hammer weight the latest type of fx and first time now trying the tungsten hammer ordered from ebay but same specs with fx .
This was a lesson for me about what can happen with so much tinkering but doesn't matter .It was an experience ...
We are lucky as fx owners that the market is full of spare parts . Even actions!!!!!
Long story short next day i am not suttisfied at all with the new 720 pp and I installed again the Poland power plenum and with the new adds ( new hammer holder and screw adjuster ,and tungsten weight ) the gun is a beast .
So far I was shooting Nsa 61.5 with amazing results at 990 fps .
Now with the new mods shooting a new round Zan 63 gr with same accuracy like before at 1058 fps .
Regulator 180 bar ,I down a little bit back the hst and closed the valve adjuster up to get the groups tighter almost at 3 and half lines.
I have a very short blast with a relatively low noise and speed 1028-1030 with a very good accuracy .
First game a crow at 110 yards .
The thump noise of zan 63 gr it was so instant at 110 yards that I didnt realise the 2 different sounds. You know the usually sound bam-thump!!!!
Completely one and instant sound in this distance with the touching of the trigger. Is a serious and noticeable difference in these high speeds from 990- to 1030 with a havy 63 gr slug .
I will post a card from strelok app with muzzle velocity at 1030 fps.
114 ft-lbf at 160 yards and 84 ft-lbf at 250 yards! Is scarry .......
Regarding the accuracy I didnt shot long range groups . But while adjusting the gun to find the sweet spot , when I managed to have many rounds almost hole to hole at 45 yards I knew I was ok .
With strelok up I am always spot on in long distances and I confirmed it by shooting small stones up to 260 meters .
Regarding my dissapoiment of the 720 pp is a very long story and I will open very soon a new thread cause if I will not find a solution with It I will not relax!
Gun 2 days after the repair .
Smoking some stones at 260 meters .
Last photo shooting an old love !
Wolverine 303 unregulated .
Since I got the impact 2019 is resting in the case ....and still keeping air !
shown here John French bestows Lexi Linder with a royal gift for winning the 1st ever Squatchbomb challenge. 
