Question for folks with Impact .25s

[sharroff]

I've got the latest generation Impact with the Ernest Rowe dual port. I have my regulator set at 100 bar and am sending my lighter (25g) pellets at like 980fps on min. I'd like to turn up the regulator to get more speed on my slugs, but don't want to 'overspeed' the 25g pellets. If I goto 110 or 120 on the regulator, can you confirm the extra resistance on the valve would slow the pellets down or am I likely to wind up supersonic (not desirable).

 

[TNT19]

Hmm if you up the reg pressure to shoot slugs it will absolutely affect the speed of your pellet. So you will want to remember your current setting for reg, hammer spring etc for pellets or you will want to shoot a heavier pellet and match a slug which will be close to what you want. 

 

[8thman]

Sounds to me that depending on what you settle on, that the jsb 34gr would be maybe where you want to be. The first thing that I would do is to shoot the slugs that you want. For my gun favorite is the nsa 36.2 slugs and it’s @860-870fps on min power, but my gun has the slug liner A and is a 700mm barrel with the regulator @110bar. The jsb 25gr out of my gun was shooting them best @890 FPS or under, but I’m mainly shooting the nsa slugs they are that good out of my impact. Good luck 

 

[qball]

Could be done. As regulator pressure goes up the force needed to open the valve will increase also and depends on how far you have the preload turned up you might actually lose speed at lower end of HS setting. In fact with higher reg pressure the lower HS force will actually drop off speed faster and much quieter. 


Up the regulator to about 120-130 and see your pellet speed is and then you can turn down the preload if you have to which won’t really affect the slug speed as much because at that regulator pressure you won’t need the HS preload maxed out at all. 

 

[2D1C]

I have a gen one Impact 700mm barrel. I added a hammer weight and a power plenum. 120bar, power setting 2, superior liner, it is right at 885 and really accurate at 100yds. If I shoot the NSA 29 or 29.5 slugs on level 4 it's 940 fps but It shoots 3" right @100yds. After correcting the windage I have actually had 3/4" groups not always? but MOA mostly. That said other's here have not had luck with that liner but the "A" slug liner does work for them. Stoti is one that has done ALOT of testing and he gets best results with the A liner for slugs. Just enjoy figuring it all out that is the fun of it for most anyway!



Dennis

 

[Butch]

For reading the op’s post, 100bar reg, 980fps with a 25 grain on min? My guess is you have you hammers spring maxed and over driving the hammer. Open your front valve to line 4, and get your 1.5mm Allen wrench out and back the tensioner out (while wheel is in the max position) till you start to loose FPS and the see where your other dial positions give you in FPS. 
you can always slow the FPS down with the front valve adjuster but why waste air. 
Butch

 

[Odoyle]

I bought extra FX Impacts in the same calibers one for pellets one for slugs. No fussing with tinkering back and fourth once you set them perfect leave them alone.

Many others have done the same as me bought multiple Impacts in the same caliber leave them alone when perfect.

 

[lancehenley1]

Yep. Get two guns or you will probably need to shoot the 34 grain pellets instead of the 25 grain. The 34 grain pellets shot well for me from 850-950.

 

[Centercut]

I have my .25 Impact X set up to shoot 43.5 NSA on Max at 895 FPS, and JSB Exact Heavy on power level 3 at 905 FPS. Both MOA at 100 yards. Power plenum, reg at 135 bar, slug A liner, FX pin probe, FX light valve spring, Ernest dual transfer port, CF tube glued on liner, 3mm thick CF tube lightly tensioned on outer barrel, STO Falx moderator. Stock hammer spring, no additional hammer weight. Easy two second shift from slugs to pellets and back.

 

[8thman]

That’s a great example I have very similar setup as far as pp slug liner A, slug pin probe power kit. But the settings for what my gun prefers are a bit different understanding that I know your setup for the nsa 43.5 and mine is for the 36.2. I believe if I started over from scratch that I may have different results? Centercut , good looking gun 

 

[qball]

I have my .25 Impact X set up to shoot 43.5 NSA on Max at 895 FPS, and JSB Exact Heavy on power level 3 at 905 FPS. Both MOA at 100 yards. Power plenum, reg at 135 bar, slug A liner, FX pin probe, FX light valve spring, Ernest dual transfer port, CF tube glued on liner, 3mm thick CF tube lightly tensioned on outer barrel, STO Falx moderator. Stock hammer spring, no additional hammer weight. Easy two second shift from slugs to pellets and back.

YUP!!! This is the beauty of Impact and FX guns in general! Back when I shot hades in my 25 impact I think I tuned the hades to about 700 FPS at Min and 29 grain slugs at around 820 fps. In .22 I had the 14.3 crosman hollow point shooting 880 at Min and 23 grain at 920 fps at 5 I think, changed my tunes too many times since then. Extremely repeatable power change, simply unbelievable!



Even my lowly dream-tac compact in .177 shoot the 7.4 grain crosman pellets at 680fps on low and min then on high and 4 shoots 12.5 grain NSA slugs at 780fps. Unbelievable adjustability with unbelievable repeatability! Every FX gun is like having 2 guns with each barrel! In fact if you get the right tunes the pellet and slugs can have the same exact zero POI, you don't even have to change scope zero!!! just a few clicks and a whole different gun!