Help needed. FX Dreamline velocities move opposite to the Power Wheel?

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ChRiSiS

ChRiSiS

Member
May 6, 2020
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CT, United States
I could really use some help here as I am not sure what is going on.

I have an FX Dreamline Tactical, with the Power Plenum and a bottle, currently with a .177 barrel kit installed. The reg is set at 100 Bar. I am seeing what seems to me to be very strange behavior, in that when the Power Wheel/Hammer Spring Wheel is set at MAX I get lower velocities than when it is set at 5,and this continues pretty much all the way down. 

Shooting JSB Exact Monster redesigned 13.43 gr pellets I get the following:

Wheel Position. 2 Avg Velocity 873 FPS; Wheel Position. 3 Avg Velocity 829.4 FPS; Wheel Position. 4 Avg Velocity 807.4 FPS; Wheel Position. 5 Avg Velocity 795 FPS

Shooting H&N Barracuda 10.65 grain pellets I got:

Wheel Position 2 Avg. Vel. 957 FPS; Position 3 AV 921 FPS; Position 4 AV 924 FPS; Position 5 922.8 FPS; Position MAX AV 899.8 FPS

In pretty much every case I get my highest speeds with the wheel at position 2 (or, in some cases when I go that low, at MIN). I have a Crown and an Impact, and have managed to tune these (or at least the Impact, since with the Crown I have really only played around with the port settings and the power wheel) successfully. However this Dreamline really has me stumped.

Any advice would be appreciated.

Chris
 
Your regulator is set to low for the hammer spring force. You need to turn down the hammer spring grub screw for the regulator setting or turn up the regulator pressure setting. The hammer is hitting the valve so hard its flying open, then maxing out and bouncing closed. Causing a faster closing then if a softer hammer hit. When the valve is hit this hard it shorten the dwell time, in turn shorting the amount of air that can race through the open seat. This is very common with new tuners and large plenums. A large plenum doesn't require the same hammer force to open the valve as the smaller high pressure plenums. One thing a large plenum needs is a longer dwell time for the valve. I recommend with your power wheel set at 5, you turn the hammer grub screw out until it doesn't building speed. Once you find the fasted speed and lowest grub screw setting. Turn the speed down 10-15fps more. This will move your speed off the peak of performance, giving you the closest SD and highest shoot count. When you move the power wheel up to Max, you'll see only 10-15 FPS. But you switch it down to 4 you should see 20-30 FPS . if your not getting the speed you need at this hammer setting you'll have to turn up the regulator setting at this point. Only turn the regulator up 3-5 bars at a time and only 1/4 turn on the grub screw at a time. And never at the same time. Only adjust the regulator after there is no speed built when the grub screw is adjusted.




 
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Thanks for the comments guys.

So, it seems as if I have two different sets of advice here. One suggestion is that I need to lower my reg pressure, the other that my hammer spring force is too high for the current reg pressure. This latter one implies that increasing my reg pressure would perhaps match it more closely to the current hammer setting.

Based on what I have seen from previous posts on all kinds of subjects so far, all these guys are credible. Basically what I am going to try (Tuesday after I get back home) is the following:

1: Lower the current reg pressure and see if that changes the behavior. That’s the simplest and easiest thing to do. If that doesn’t change the behavior (i.e. where my higher hammer settings give lower velocities) then I go to step 2, namely:

2. Turn down the hammer spring as per Mrshosted and follow through with his suggestion.

More comments would be welcomed. It is a bit of a pain in the backside, but it’s kinda neat, interesting and a learning experience too.

Chris
 
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Very typical of too much hammer spring for your regulator.


Easy test: put your power wheel on 5 and then increase the regulator pressure which can be done anytime. Turn the regulator screw counter clock wise 1/4 a turn at a time, You should hear a hiss and regulator pressure goes up a little. . Your speed should go up significantly with each 10 bar increase. 
 
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While I agree that most pellets like sub 900 the monster redesign can be accurate in the lower 900 or even close to 1000 FPS range. His gun have too much hammer spring but that particular ammo can use a little upper range in speed. He probably will only need 110-120 bars to get to that speed and in the end he will need to back off hammer spring regardless because it is most likely setting 3 or 4 will have the fastest speed. Then all he has to do is back the hammer spring adjust screw so the max is around where he wants the top speed be. Redesigned monster can shoot accurately at close to 1000 FPS. Not something I would do but could be what the OP wants and I don’t see anything wrong with it. 
 
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I'm assuming your goal is to have the gun tuned for the most accurate speed and power level, having the highest shoot count. If your worried about my advice, count the turns out on your grub screw as you back it out. You'll be able to return it back with out any problems. Yes Id agree a .177 with a smaller plenum could have a regulator set point of 100-110 to shot about 900 FPS. But with the larger plenum Id hope your regulator will be closer to 85-90 bar, with your level 5 pw shooting 900 FPS. With a .177 in the Dreamline shooting pellets, your factory plenum was more then big enough. The larger plenums don't offer much improvement until the power level excides the one CC's of plenum to one FPE. 

As everyone has stated, way too much hammer spring for the reg pressure. 

If your swapping back and forth between 2 calibers and happy with 870, leave it and shoot on setting 2. If not, you have some tuning to do.
Click to expand...

Rj has a very good point. 
 
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Thanks everyone for the comments. I haven’t yet had a chance to go and change things, but there seems to be a consensus being generated by one group that I have too much hammer spring for the Reg Pressure (which is currently set for 100 Bar by the way).

Keyman62421 seems to think that I am simply seeking power, Power, POWER 😂. I am not sure why he thinks that, since I certainly didn’t say it in my OP. What I would like is to get the easy and predictable adjustability that comes with changing the power wheel, and to my mind is one of the key attractions of the FX guns to me. I have this on my Crown, as well as on my Impact, but not so far on the Dreamline.

In any event it should be simple (I hope 🤞🏼) to do a couple of adjustments over the Chrono and see how things change, since the reg pressure is pretty easy to adjust up and down. Then, based on that, I will pick one reg pressure and adjust the hammer spring for less tension, all while checking what I get for velocity changes. 

It may yet be that I will be stuck in the dilemma outlined above by R5, in that I do want to switch between calibers (and it was working fine as a .25) and so might be better off just shooting the dam thing on one setting so as to not have to retune if/when I switch back to .25.

I should add that the gun was a laser as a .25 at both 25 and 50 yards. Even with my issues the .177barrel is shooting pretty accurately, although so far I have really I only been testing velocities at 15 yards in my basement.



Chris
 
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I'm assuming your goal is to have the gun tuned for the most accurate speed and power level, having the highest shoot count. If your worried about my advice, count the turns out on your grub screw as you back it out. You'll be able to return it back with out any problems. Yes Id agree a .177 with a smaller plenum could have a regulator set point of 100-110 to shot about 900 FPS. But with the larger plenum Id hope your regulator will be closer to 85-90 bar, with your level 5 pw shooting 900 FPS. With a .177 in the Dreamline shooting pellets, your factory plenum was more then big enough. The larger plenums don't offer much improvement until the power level excides the one CC's of plenum to one FPE. 

As everyone has stated, way too much hammer spring for the reg pressure. 

If your swapping back and forth between 2 calibers and happy with 870, leave it and shoot on setting 2. If not, you have some tuning to do.
Click to expand...

Rj has a very good point.
Click to expand...

I actually thought that your advice was pretty coherent, and while on the surface it seemed to be the opposite of what others were saying, if you look into both sets of approaches there is actually a great deal of common ground between them. You just went into it a little more deeply and outlined the possible reasons for the discrepancies I am seeing. In any event, your approach makes sense to me and I did intend to count the turns on the hammer spring so that i could get back to where I started. I think you are probably spot omen about the larger plenum, And its quite easy to change the reg pressure, so i will try the lower pressure for sure and see what I get.



Thanks for all the help guys!

Chris
 
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have you had your power wheel off? they will fit upside down?? been there done that..
Click to expand...

That I had not thought of 😬

I have not taken the power wheel off, but the gun was a used one, so it is possible that it was off and reinstalled improperly in one of its prior lives!

For now I am going to bury my head in the sand and forget that I even saw your comment 😂
 
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So, after messing around and firing a bazillion rounds through the Chrono (OK, only about 7 mags) Here is where I have ended up.

I backed the hammer screw out multiple times. I clearly had much too much hammer tension, as numerous people mentioned, since my velocity went UP on the higher settings as I Initially decreased the hammer tension. When I got to where less hammer spring actually led to decrease in velocity I started to play with reg pressure. Down at 90 Bar however I really started to see lots of inconsistencies in speed. Normally this gun gives about a 10 FPS extreme Spread. At 90 Bar (I didn’t go below) I was seeing the speed bounce all over the place, with eS of up to 25 or in one case 30 FPS. 100 Bar was a lot better, and at 110 Bar I got very good consistency. In addition, while I didn’t get much variation when I adjusted the power wheel I did see a clear difference between the positions. For Example, using H&N Barracuda 10.65 grain pellets 5 = 957 FPS; 4 = 947 FPS, 3 = 944 FPS, 2 = 943 FPS and 1 also 943 FPS. 

With the Monster redesigns (13.43 gr) I get 5 = 886; 4 = 887; 3= 870; 2 = 871; 1 = 859

So, my original hammer spring was much too high for my reg pressure, but it seems like I needed to both increase reg pressure while I dialed down the hammer spring. At least now I can make some sense of what happens when I turn my power wheel. There I s a lot more playing around that I can and will do, but the hour is getting late here and i have a 7:30 AM video meeting I have to be on in the morning, so I am going to leave things as they are.

Thanks to everyone for the advice, especially to those who took the time to explain what they thought was going on in some detail. Turns out that almost everyone was right to some extent, as i had clearly buggered things up quite significantly. Now I at least am beginning to understand the dynamic nature of the interaction between the various adjustment.

That’s really the great thing about AGN.

Thanks again and stay safe everyone.

Chris
 
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