FX impact power wheel not changing fps

[Hudo]

Hi all, 

I just replaced the clapped out c3 bumper with Delron in stock impact gen 1v2. 600mm slug liner.

At 100 bar getting 900fps and 120bar getting 960fps with JSB18gr. 

The power wheel is working/turning but not changing the fps? Hammerspring adj is maxed up..

What am I missing here?

 

[ImpactX]

Reg pressure need to be higher. My impact reg at 130bar with PP, wheel 3, 4 ,5 and max give the same fps. But if I crank up the reg to 140bar, 5 and max give more fps than 3 and 4. So if your power wheel isnt giving anymore fps, crank up the reg pressure. 

 

[qball]

^^^^^^^that! 


also check to see if the valve is shut too tight. 

 

[Hudo]

I don't think the valve is the issue, I'm wondering why there is no difference between min and max? Like 10fps ? 

 

[cmatera]

My Impact Compact PP has the reg set at 100. I tested every setting. The difference was from 913 fps to 902 fps. A friend who has had an Impact longer than I said there’s not much adjustment using just the power wheel.

 

[Rj]

Hammerspring adj is maxed up..

What was your purpose for doing that? ^^

 

[Hudo]

Hammerspring adj is maxed up..

What was your purpose for doing that? ^^

Most tuning guides r3comend it for heavy pellets and higher reg pressure...

Unless I'm retarded -by having the hammer on full at max means that when you reduce the power wheel down the hammerspring is moving back less... hence my question as to what is going on that reducing the powerwheel doesnt seem to be having any effect, so maybe I've got the hammerspring up too tight (even on min) for the pressure im running on the regulator, so either pump up the reg pressure or reduce hammerspring...?

 

[Rj]

Hammerspring adj is maxed up..

What was your purpose for doing that? ^^

Most tuning guides r3comend it for heavy pellets and higher reg pressure...

Unless I'm retarded -by having the hammer on full at max means that when you reduce the power wheel down the hammerspring is moving back less... hence my question as to what is going on that reducing the powerwheel doesnt seem to be having any effect, so maybe I've got the hammerspring up too tight (even on min) for the pressure im running on the regulator, so either pump up the reg pressure or reduce hammerspring...?

That's what I think is happening. Try 145- 150 bar.

 

[Eaglebeak]

I seem to remember Ernest explaining that when you replace the O-ring with the Delrin washer, you lose the ability to tune the power down using the valve stop ( power adjuster ). That is the reason that they didn't fit them that way at the factory. It will be in an old thread from 2-3 years ago.

 

[biohazardman]

Try backing off the power adjuster Allen screw. It will probly need backed off quite a bit. That is how I got a portion of my power wheel adjustment back after adding a hammer washer/weight and installing the Delrin C3. Increasing the reg might werq also but will put you at a higher fpe level.

 

[edosan]

Try backing off the power adjuster Allen screw. It will probly need backed off quite a bit. That is how I got a portion of my power wheel adjustment back after adding a hammer washer/weight and installing the Delrin C3. Increasing the reg might werq also but will put you at a higher fpe level.

That

If the wheel do not change the speed is because the spring has too much tension, you need to unscrew a bit the hammer spring tension screw

 

[Kitplanenut]

Hudo. Your not alone. Have been having the exact same thing with my gen 1 Impact. Had the gun apart several times inspecting and changing the C3 bumper. Backed the hammer screw in and out. still no change. Changed out the reg to a Huma, but have not tried the upper pressures yet. mostly working around the 110-130 range. Thing that really bugs me is that there is no change in fps at all. Questioned if the valve rod had unscrewed or gotten changed somehow. Took everything apart measured and locktighted all together. Reassembled still no change. I'm running out of o-rings chasing this gremlin. And running out of things to try. It CAN NOT be that complicated! Thinking of ordering a power plenum kit then they are available and giving that a try. What I've tried has not worked. Maybe throwing $ at it will fix the problem. sylvan

 

[Revoman]

Although this is about a Crown Continuum tune, there is some important information about the adjustments on the wheel. Actually the entire tune starts around 50:00 minutes in, but the talk about the wheel adjustment is more toward the end. Steve explains that if it's tightened too far, there will be little adjustment with the wheel.

https://www.youtube.com/watch?v=Dzs_muWHE5s

mike

 

[Hudo]

Thanks all, I've wound up the pressure, still bugger all change. I can't get it as if you drop it to min it has eased off the hammer spring immensely. It seems to be adjusting it about 20fps between max and min

 

[triggertreat]

I would back off on the spring while at max, and while shooting over the chrony. Once you start to see the velocity drop with spring adjustment then go back in a smidge. Then when turning down the wheel you should see a change. If wound up too much, I wouldn't expect to see much of a change.

 

[lancehenley1]

Mine makes adjustments. the weird thing is, it will shoot faster on power setting 3 than it does on max. not sure why that is.

 

[lancehenley1]

Got my .25 shooting 25 grain jsb on Min at 960. and i go to 3 or max on the power wheel and shoot 34 jsb around 880. both are shooting quite well at those speeds.

 

[tor47]

Mine makes adjustments. the weird thing is, it will shoot faster on power setting 3 than it does on max. not sure why that is.

You probably has to much tension on the allen screw, on the power adjuster.

The hammer spring can be adjusted to much, making the valve bouncing back faster and closing earlier, than it would with less spring force. I know some owners used to tune theire guns by adjusting the allen screw on the wheel all the way to the max, but I do not think that is a good advise now. It probably was no problem doing so on the older impacts in caliber .25 and up, as they usually required high pressure when shooting heavy pellets. In caliber .22 and especially if you have a mk2 gun with power plenum, the allen screw can easily be adjusted to much. 

 

[tor47]

The old C3 bumper acted as a cushion when the hammer hit it. By replacing it with a delrin bumper which is harder, the hammer force hitting the valve rod will increase even if you do not change any settings on the gun. So if you replace the old c3 bumper for a new delrin one, you probably has to turn the allen srew out on the powerwheel, to have the same adjustements on the wheel as before.

 

[tor47]

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.