Umarex Another Notos question?

My Notos does not shoot decent (5) shot groups at 25 yds until the air tube PSI gets down to around 2,600PSI. It then shoots (5) shot groups of around .5". Above the 2,600 PSI it throws quite a few flyers. The speed when it's above 3,000 PSI is around 740 fps. At 2,600 PSI the speed is just over 700 fps. I'm shooting the JSB 15.89 gr Hades pellet. Anyone have an idea why it does this? Thanks, 20PPC
 
My Notos does not shoot decent (5) shot groups at 25 yds until the air tube PSI gets down to around 2,600PSI. It then shoots (5) shot groups of around .5". Above the 2,600 PSI it throws quite a few flyers. The speed when it's above 3,000 PSI is around 740 fps. At 2,600 PSI the speed is just over 700 fps. I'm shooting the JSB 15.89 gr Hades pellet. Anyone have an idea why it does this? Thanks, 20PPC
I was going to recommend trying the 18 grain jsb too, or any heavier pellet just to see if keeping things in the barrel a ms longer helps.

The other thing I might suggest listening for air waste. This is sort of a learned thing so don't sweat it if you can't hear it. Wooshes or poofs after the shot would indicate to me that there is a large volume of wasted air coming out behind the pellet to disturb it. The notos is regulated, but even my fx guns with regulators (one with 2) have preferred fill points for prime accuracy. Best of luck on working this one out!
 
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Reg or hammer settings.

You can get an inexpensive 1:1 spa pp750 reg from ebay. Sometimes regs will creep during fill. Your hammer may be low in the range. But sounds like youre creeping. Your reg may be set ridiculously high because that's how unregged guns behave.


Have you screwed your hammer spring adjuster all the in/out

The first shots are they really quiet?
 
Reg or hammer settings.

You can get an inexpensive 1:1 spa pp750 reg from ebay. Sometimes regs will creep during fill. Your hammer may be low in the range. But sounds like youre creeping. Your reg may be set ridiculously high because that's how unregged guns behave.


Have you screwed your hammer spring adjuster all the in/out

The first shots are they really quiet?
I have not messed with the hammer spring adjuster, but I will take a look at it. The first shots are kinda loud. It takes several shots before it settles down. I'll probable try a new reg.

Thanks for the info guys. 20PPC
 
After mulling this over, I'm kinda leaning toward a regulator problem. Attached is some early 3-shot groups I shot at 25 yds with the JSB 15.89 gr Hades pellets. I'm kinda ruling the pellet problem out at this point.

Thanks again.

IMG_1021.jpg


IMG_1004.jpg
 
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After mulling this over, I'm kinda leaning toward a regulator problem. Attached is some early 3-shot groups I shot at 25 yds with the JSB 15.89 gr Hades pellets. I'm kinda ruling the pellet problem out at this point.

Thanks again.

View attachment 584366

View attachment 584367
Reg would be my first diagnosis if hammer hasn't been adjusted to the max and bottomed out. Sounds like youre opening the valve and getting a giant blast.
 
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Reg would be my first diagnosis if hammer hasn't been adjusted to the max and bottomed out. Sounds like youre opening the valve and getting a giant blast.
Exactly my my thought as well. If you can tell by ear when a 2 stroke is running clean, you can learn to hear wasteful muzzle blast or hammer bounce. My circle refers to this as "tribal knowledge" and I'm Greybeard The Wise Wizard that dragged them down the rabbit hole, keeper of unexplainable tribal knowledge. But I can show it.
 
Exactly my my thought as well. If you can tell by ear when a 2 stroke is running clean, you can learn to hear wasteful muzzle blast or hammer bounce. My circle refers to this as "tribal knowledge" and I'm Greybeard The Wise Wizard that dragged them down the rabbit hole, keeper of unexplainable tribal knowledge. But I can show it.
Ear is the best way to adjust hammer and valve.
 
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Let me grab my rattlesnakes and 2 pygmy witch doctors to translate my venom and ayuhuasca induced psycho rambling babble into "truth" be right over. Watching with my 3rd eye
You have no idea how close you are on the snake. I don't want to derail too much so back to the deal.

If the reg fails, it should be prone to valve lock or have a much faster valve event. Is the valve being slowed?
 
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