Tuning Impact m3 .177 tuning

[okieairgunner]

Ok wonderful people. I’m a little stuck with my impact. I have a m3 first reg is on 150 power wheel on 8 and micro wheel on 3 2 reg on 90. Valve on 4. I’m setting up a bird gun shooting .177 jsb 13.43 at about 980fps but it’s shooting 920’s not matter what setting I have it on on the power wheel. I also have a dual TP and pin probe. What I am trying to do is set up my gun shooting 980fps on 8 for room to go down to shoot lighter like 10.34 and room to go up to shoot slugs. I appreciate any help. And yes I am a noob but love learning.

 

[Jayson]

So I don’t go way deep in detail, but I have set up a couple with that slug, you are way low on the second reg, which is why it won’t go up as you mash that valve that is a tuff little slug to get moving and not a lot of surface area, I’m guessing to tune it right! Not this low pressure crud, you will be around 120 bar, assuming your gauge is correct and keep that front valve adjuster out at 4 or more, make that move up slowly and your velocity will follow, I don’t recommend touching anything other than reg first, keep going up until she starts to shoot down, then go up 1 number on the power wheel, repeat process until you get your speed. Btw, that is really fast for birds? It will shoot great @ 900-950 Listen to the gun, if it really doesn’t want to go faster, don’t push it, you won’t regret it.


good luck

 

[5thumbs]

I'm following with interest. Just got a .177 600mm myself from SPAW. Ken tuned it for 12 FPE and 20 FPE for me (my request). Way shy of what your trying to achieve, but I to am interested as there seems to be much less info on the .177 M3

 

[okieairgunner]

So I don’t go way deep in detail, but I have set up a couple with that slug, you are way low on the second reg, which is why it won’t go up as you mash that valve

that is a tuff little slug to get moving and not a lot of surface area, I’m guessing to tune it right! Not this low pressure crud, you will be around 120 bar, assuming your gauge is correct and keep that front valve adjuster out at 4 or more, make that move up slowly and your velocity will follow, I don’t recommend touching anything other than reg first, keep going up until she starts to shoot down, then go up 1 number on the power wheel, repeat process until you get your speed. Btw, that is really fast for birds? It will shoot great @ 900-950

Listen to the gun, if it really doesn’t want to go faster, don’t push it, you won’t regret it.


good luck

Jayson 

I really appreciate your time sir. First this I wanted to state is that I am shooting the jsb 13.43 pellet. But was stating I would like to be able to quickly go up in power to shoot slugs without changing a whole lot of things on my tune. 

I wanted to shoot the jsb pellets at 980 FPS because that is what my wildcat mk3 was originally set up to do. And it was a laser. With almost 30 fpe I was able to reach out and touch things like squirrels and birds and other things at 70 plus yards with .177. Also I have this barrel laying around and thought it would be fun and cheaper to shoot the .177 more. Whole heck of a lot of shots. 

 

[nervoustrig]

I’m setting up a bird gun shooting .177 jsb 13.43 at about 980fps...

Wait, have some rogue quetzalcoatlus escaped from John Hammond's island?

Just having some fun. Makes sense if you're wanting it set up as a dual purpose pellet & slug gun, and planning to reach out to longer-than-usual distances for .177.

 

[okieairgunner]

So I don’t go way deep in detail, but I have set up a couple with that slug, you are way low on the second reg, which is why it won’t go up as you mash that valve

that is a tuff little slug to get moving and not a lot of surface area, I’m guessing to tune it right! Not this low pressure crud, you will be around 120 bar, assuming your gauge is correct and keep that front valve adjuster out at 4 or more, make that move up slowly and your velocity will follow, I don’t recommend touching anything other than reg first, keep going up until she starts to shoot down, then go up 1 number on the power wheel, repeat process until you get your speed. Btw, that is really fast for birds? It will shoot great @ 900-950

Listen to the gun, if it really doesn’t want to go faster, don’t push it, you won’t regret it.


good luck

jayson. 

I also tried raising my 2nd reg pressure to 110 bar both wheels were maxed out. Quick tune to where it would just cock and the pw on 16. I was shooting the pellets at 1000 FPS which was great. But this is what confused me. I started turning PW down to see what kind of number I would get and 16-1 on the pw it stayed at 1000 FPS so I am confused still lol

 

[okieairgunner]

I'm following with interest. Just got a .177 600mm myself from SPAW. Ken tuned it for 12 FPE and 20 FPE for me (my request). Way shy of what your trying to achieve, but I to am interested as there seems to be much less info on the .177 M3

He is great man. Just kind hard to get ahold of sometimes. I got my mk3 wildcat compact from him in .177. Actually I took the barrel kit off it to put it on the impact. (Wildcat is now a sniper shooting amazing in .22) The wildcat came to me from him shooting these pellets at 980 like a laser. So I know it can me done. I asked him to tune it for longer range shooting and he suggested the 13.43 jsb pellet. If the wildcat can do it I KNOW the m3 can. 

 

[Jayson]

So I don’t go way deep in detail, but I have set up a couple with that slug, you are way low on the second reg, which is why it won’t go up as you mash that valve

that is a tuff little slug to get moving and not a lot of surface area, I’m guessing to tune it right! Not this low pressure crud, you will be around 120 bar, assuming your gauge is correct and keep that front valve adjuster out at 4 or more, make that move up slowly and your velocity will follow, I don’t recommend touching anything other than reg first, keep going up until she starts to shoot down, then go up 1 number on the power wheel, repeat process until you get your speed. Btw, that is really fast for birds? It will shoot great @ 900-950

Listen to the gun, if it really doesn’t want to go faster, don’t push it, you won’t regret it.


good luck

jayson. 

I also tried raising my 2nd reg pressure to 110 bar both wheels were maxed out. Quick tune to where it would just cock and the pw on 16. I was shooting the pellets at 1000 FPS which was great. But this is what confused me. I started turning PW down to see what kind of number I would get and 16-1 on the pw it stayed at 1000 FPS so I am confused still lol

So please remember to only adj one thing at a time! If you get in a pickle? (This is important! ) go back and start over! What was it doing at 105? 100bar? If every impact owner that is trying to learn would simply do this, they would really make it easy on themselves 
Just start over! It’s a great process, turn hammer and reg way down and work back up, nothing else, front valve adjustment is last, the only mistake I see often with that is people start with it at line 1 or 2, that it pretty restrictive and hard to get past. So don’t do that to yourself
good luck and sorry for missing the slug pellet thing, but same concept right? 

 

[Corvid_hunter]

I think I read somewhere that if the reg pressure is too high and the hammer spring is too low there will be no difference when you adjust the power wheel. Or maybe that's backwards. My MKII with the dual Huma dual TP and pellet probe I can shoot 35gr (.25cal) slugs at 900fps with the valve turned down, and about 930-940fps on line 4 with 110 bar on the reg. I would try going down to 80 or 90 bar on the reg and restarting the tune. I'm also getting approx 100 shots per fill.

 

[177er]

I don't know (or understand) why some people are recommending too much reg for 177. Could you provide more clarity on why a super high reg is necessary for a 10 grain pellet? In my experience, there is no benefit in going over 60 - this is only specific to the Impact.

Here are some settings I use with my Impact MKII

1) Shooting 8-9 gr pellets at 900 - 925 - Reg at 50, HS tension to min and Wheel setting to max. Valve line at 1

2) Shooting 13 gr at 900ish - Reg at 65-85, HS to somewhat more than minimum. Wheel to your speed, and Valve again at lowest.

3) Shooting 16.7g slugs at 920-940. This is where it gets tricky. The slugs are a tight fit, and I have to turn up the reg to get good speeds. Reg at 135, HS in the middle, and wheel at max. Valve at 2 lines.

I would like to again quote @tor47 from a previous post somewhere.


To illustrate: If you have a impact mk2 with power plenum in .177, it is likely the gun will be delivered from factory where the power wheel does not start to add tension on the hammer spring until you are at "4", or "5", and the gun will still shoot 880-900 fps with jsb heavy at "5", or "max". The lowest speed from "4" and down to "min" may be 850-860. The reg will probably be around 90-100 bar. I would guess only a .22, or .25 actually would have all the settings on the wheel "working" when delivered from factory. Any low power shooting will require adjusting in the valve adjuster, as even setting the wheel on "min" will make the gun to shoot to fast.

The only addition I'll say is that you don't need to go too high on the reg to achieve fairly good speeds.

Adjust 1 thing at a time, note the chrono readings, and then note your settings for that adjustment, and then do any other adjustments.

I will also say this. I cannot get the Impact 177 to be a dual shooter with 1 tune. My pellet tunes are at 50-70 bar and the slug tune is 120 bar+ with different settings.
However, it is VERY easy to tune it, I can do this in less than 5 minutes, with just a couple of speed readings.



Sample tunes.







I added the dual transfer port recently and have been able to shoot 16.7 gr slugs at 930-940 at a reg setting of 135, it's made a big difference compared to the pellet transfer port.

Edit: Here is the link to the earlier post .

https://www.airgunnation.com/topic/fx-impact-power-wheel-not-changing-fps/