I resently got myself a 700mm pellet barrel kit for my impact. It had a .177 kit on it wich I have tuned to shot around 880fps with 115 bar reg pressure. Since my new .25 barrel seems to foul up quickly with lead near the choke, it probably needs some thousands of pellets true it to get better. In that regard I am planning to not shoot to fast, as I think going beyond like 900fps will foul up barrel even quicker.
I first tested the gun over a chrony with the previous set 115 bar, and discovered I could go beyond 950 fps with a 25 grain pellet. I then lowered the pressure to 100 bar and started with low hammer spring tension, and the gun peaked at about 880-890 or so on max speed. But the gun seemed to be more air efficient at the previous 115 bar. I am for the time being planing to shoot about 830 fps, and to achieve that speed I can use quiet low regpressure. But somehow I feel a litle uncomfortable using that low pressure on a .25 caliber setup. So I upped it a lilte to 105 bar, and the gun peeks at about 900 fps. Still more than I need to achieve the 830 range. I am btw using a edgun digital gauge to read the regpressure, so I beleive it is quiet accurate.
The question is: Will the gun be more efficient with air if I rise the regpressure to like 120-125bar, and just control the 830 range speed with hammer, and valve adjuster instead?
The reason I ask, is that even I can achieve high speed with relative low regpressure, I guess the gun is emptying the plenum quiet a bit, and will see a relative high pressure drop inside the plenum filling a long .25 barrel with only 105 bar? Following that logic higher pressure will in that regard lead to less air having to be released from the plenum, and make the gun more efficient. I can offcorse just test it myself, but wondered if anyone else has done similiar testing with a quiet unusual tune on an impact?
I first tested the gun over a chrony with the previous set 115 bar, and discovered I could go beyond 950 fps with a 25 grain pellet. I then lowered the pressure to 100 bar and started with low hammer spring tension, and the gun peaked at about 880-890 or so on max speed. But the gun seemed to be more air efficient at the previous 115 bar. I am for the time being planing to shoot about 830 fps, and to achieve that speed I can use quiet low regpressure. But somehow I feel a litle uncomfortable using that low pressure on a .25 caliber setup. So I upped it a lilte to 105 bar, and the gun peeks at about 900 fps. Still more than I need to achieve the 830 range. I am btw using a edgun digital gauge to read the regpressure, so I beleive it is quiet accurate.
The question is: Will the gun be more efficient with air if I rise the regpressure to like 120-125bar, and just control the 830 range speed with hammer, and valve adjuster instead?
The reason I ask, is that even I can achieve high speed with relative low regpressure, I guess the gun is emptying the plenum quiet a bit, and will see a relative high pressure drop inside the plenum filling a long .25 barrel with only 105 bar? Following that logic higher pressure will in that regard lead to less air having to be released from the plenum, and make the gun more efficient. I can offcorse just test it myself, but wondered if anyone else has done similiar testing with a quiet unusual tune on an impact?
