Umarex Notos O ring List- Lets put them ALL here

Mark,

Yes, I saw the front site location. I haven't looked at the pic rail yet to see how it's attached though.

Yes, the barrel orings are a mess, I am looking to find suitable replacents for us all.
pic rail is all one piece and part of the shroud.. only separate items are the barrel, shroud tube and a rear not threaded bushing
 
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I installed the 1mm CS x 10mm ID rings yesterday. They were tight enough I needed to lightly hammer the barrel in with a 2x4 piece..
I thought hey that's gotta be good-make a seal.

Here are results with FX Atomics

Full pressure
1 complete HS turn in from all the way out (I think 1st shot low b/c I had silicone grease everywhere lol)

730.5, 739.1, 740.9, 739.1, 741.8, 744.4, 741.8, 740, 743.6, 742.7, 745.3, 743.6, 743.6, 744.4, 748.9, 750.7, 745.3, 743.6, 748, 742.7, 747.1, 750.7, 749.8, 740.9

End ~2,400 psi left (took 24 shots, obviously could shoot more to my 1.9k reg dropoff but it was 2 CARM mags and the last of my tin)
Ave FPS 743.6875
Ave FPE 19.53

It was more than before I installed the plenum kit by 5 FPS but it's making me wonder if I should also try to replace the inner o ring (one bolt goes through).

I have enough extras that I may try it out but in the meantime I did order these that @billhill got from Ali. I did 55 sets which got me >$20 so I got $3 off coupon. I think it means I'm getting 550 0.8mmx10.2mm rings coming on a slow boat.

Just ridiculous we can't have standard sizes... makes me want a lathe to widen the o ring slots in the OD of the barrel so we can use 1mm CS x 10mm or 10.5mm rings.

Where are people at for shot count? I just passed 1,000 pellets. Wondering if that makes my spring broken in and it is a normal amount of gain for plenum. I need to play with it to see where 97% of max FPS will get me with what HS setting so it is more efficient.

Also, sorry haven't gotten the dB meter out recently, I've been busy. But I did get a non tapered Buck Rail to test out.
 
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Hi from the UK.

Really helpful Post guys.

I’ve just resealed a Stoeger XM1 Bullpup which has many similarities to the model subject of this post.

There are some slight differences, but most hard to source O rings can be replaced with close sizes. For example the reg body (54) can be replaced with 21 x 3mm and the reg piston small end a BS006 2.90 x 1.78, I used 3 x 1.5mm and it worked fine.
 
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Hi from the UK.

Really helpful Post guys.

I’ve just resealed a Stoeger XM1 Bullpup which has many similarities to the model subject of this post.

There are some slight differences, but most hard to source O rings can be replaced with close sizes. For example the reg body (54) can be replaced with 21 x 3mm and the reg piston small end a BS006 2.90 x 1.78, I used 3 x 1.5mm and it worked fine.
unfortunately there's no good close ones for the barrel to breach in either metric or standard, I was about to turn the the groove out to fit a regular metric o ring but it was nice firewalker has them available..
thank you firewalker 😀😊
Mark
 
unfortunately there's no good close ones for the barrel to breach in either metric or standard, I was about to turn the the groove out to fit a regular metric o ring but it was nice firewalker has them available..
thank you firewalker 😀😊
Mark

Hi Mark,
Thanks for your reply. The Stoeger XM1BP, Snowpeak P35 and Remington Spirit (all the same guns) are slightly different and not so problematic to get seals for, many are standard metric which I already had as they’re common to other guns.

The XM1BP has cylinder seals at 22.5 x 2.5mm, the barrels support seals are 9 x 1.5mm and the reg piston small end is 3 x 1.5mm. There’s nothing to say the specifications on older models might vary and as usual the information available from the factory is scant at best.
 
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