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Tuning Sorry another FX Impact tuning question

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L

Lemensd

Member
May 18, 2018
262
5
TX, United States
I have replaced the orings twice on my regulator plus the probe oring and tuned to no end but keep getting a extreme spread of around 15 fps when previously could get about 8. While I know this isn't the end of the world my obtainable extreme spread was easy to achieve.

My accuracy is excellent and efficient but cannot lower my extreme spread. I'm thinking something something on my valve rod assembly?

Myr muzzle report sounds low but the breach end has a pop to it, again I've replaced the probe oring twice.

Any help appreciated.

Donald




 
Are you inspecting weighing and lubing your pellets? I opened up a new tin of pellets awhile back both extreme spread and accuracy went to crap. I tried a few things but the pellets were suspect right away as I had no problems before I opened up that new tin. So, I inspected and sorted through some of my pellets and found them to be way inconsistent in both size and weight compared to the prior tin. Not much one can do about it but sort through them or find another pellet the werqs well in your gun. Put them in separate containers according to weight and size and problem solved.

Also it sometimes takes a while for the new o-rings in your reg to settle in give it a couple hundred shots to do so anyway.

A slight change in reg pressure or hammer spring tension could take you to a new place with your extreme spread as well.

Good luck in your endeavor.
 
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Vet.

I already replaced the two on the transfer port.

Bio

Haven't sorted but have older and newer from other brands known to be made by JSB all same results, and the reg has had time to settle and had same results before changing orings.

If I hurry shots velocity drops then pretty much settles, if I wait a minute the velocity stays higher.

An example

917-915-908-904, hurry next two shots-892-902-905-906-wait couple minutes- 912-909-901-904

Pausing between shot for at least 30 seconds.

And no regulator creep at all.

Can the valve rod assembly cause this effect? Plus I've tuned the living daylights out of trying to chase this down.

I'm know expert but have always had good results.

Donald
 
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I recently put a new reg in mine because of other changes I made. It amazing how long it takes for it to settle when you have the impact figured out so much that you don’t have to fire one million shots to get it tuned. I had mine dialed back in with probably 50 shots. That’s not near enough for a new reg to settle as I’m finding out. At least you have no creep. I’d take a 20fps ES over a 5b creep any day when it comes to slugs and an Impact. 
 
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Vet

I have a new Huma gen3 but when I installed it the Huma website instructions were incorrect on the spring count and stack for the model I have, so I tried a different spring stack arrangement and didn't work right, it was a weekend and couldn't get information, so I just cleaned lubed new oring.the FX and reinstalled. Maybe I will reinstall the Huma now I know the spring arrangement.

I have also tried two different chronographs.

My accuracy is so good now I don't really want to try the Huma. I'm just kinda ignoring the ES now and shooting as is hoping it will settle down...but yesterday when I got home I had to shoot a few over the chrony and the shots above were the results.lol

Donald
 
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I have had a Huma in its bag since I bought my Impact. Was tempted to install it this time when I had things apart but also had a new AMP so I just dressed up the piston and seat then installed it. My original AMP was a good reg and after dressing all my washers with 2000 grit, it’s response time was instant. I use two regs on my Impact so it’s understandable that the second regs break in time would be double. Having that Huma is like a chocolate chip cookie sitting on the coffee table. It’s hard to leave it alone. Glad you said something about the washer stack being wrong on the website. If you have a MKll PP, I may have to shoot you a PM if I ever decide to install mine to get the proper orientation.
 
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