Finished today. Leaving stock as is for now. But I got a plenum on behind the drop... Also full port to 4.0mm, 1980psi, 855fps with 15.9. I am happy. Still tighter than a bullfrogs ass with JSB/JTS 15.9/16.08 and 17.5 218 NSA slugs.
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Umarex My Notos first impressions
- Thread starter phoenix_cow
- Start date
I decided to try and port mine. I have it completely disassembled now. I do have one question; Do you have to drill out the brass part (valve) the pin was holding? It seems like you should but I don't want to drill it out if I don't have too.
I also bit the bullet and ordered parts to do a bottle conversion. Looks like the same stuff that KatoKevin454 used. Someone made a great video of how to do it on youtube recently.
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Just the transfer port. The part that you screw the airtube onto. And the hole to the transfer port from the valve to tp
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Id go straight to 4mm if I were you. Pussy footing just prolongs the suffering. I hate having to completely crack the gun back open
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4 mm or 4.5 mm ?
I thought most people porting the Notos, were enlarging the ports to 4.5mm.
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I was going to go 4mm. Taking apart the gun was a bit of a hassle and I have to travel to get access to a drill press, it's at my dad's shop. Rather not be bothered going back unless I have too.
Not sure how a 4.5mm will work, a 4mm barely fits without hitting the threads in the hole you have to go down to port the TP. Unless you wanted to tap the hole and find a screw for it. Although maybe I'm missing something.
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Yes
The goal is to increase the air path. If you don't open the port from or to the valve (the brass is the valve seat) you restrict the airflow.
Also, the reasoning behind the 4.5mm porting size is simple: You would have to drill out the TP hole threads to go larger.
Not a big deal but you need to then drill and tap the TP access hole for an M6 screw and re make the o-ring seat.
You need to drill and ream the air block, valve body, transfer port as well as the barrel to see a full uninterrupted airflow.
This is why I had c88machining make me these 3-hole thimbles for my Notos.
No bottlenecks, no restrictions.
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I have the same for my FX barrel conversion. The mk1 with the oversized port had issues with slugs and some pellets getting caught on the hole. Very Happy with mk2 which he sent me for free.
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4.5 you will need to tap and make a new oring seat for the access screw. I did 3.7 first. Gained 50fps, gun ran incredibly well. No signs of turbulence. Went to 4.0 gained another 11fps. At higher hammer spring tension. Im seeing a giant burst of air and some turbulence. I've had to reduce pressures and hst to match the pressure for peak accuracy. Same with How higher end guns could easily break the sound barrier with pellets. But people keep them between 860 and 920. I can sling 16gr at 860 out of my 380mm barrel.. but I get much better results at 800.
Currently the best performance in getting is 1950psi with the hammer spring at about 35-40% 794-802. I could also degas and play the pressures... But man it sucks degassing a 500cc tank and filling to have to do it immediately if the results arent to my liking.
I suspect a 500mm barrel might help boost the velocity in a more stable way. I'
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This is not correct.
4.5mm is the threaded opening diameter, porting to 4.5mm is not only possible but I've ported dozens of Notos to 4.5mm without issue.
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Done with the port job. I did 4mm. I really didn't want to have to tap and all that.
Did some quick tests. Hades is now shooting at 800fps. NSA 17.5gr is at 760fps. NSA 20.2gr is at 710fps. I am happy with these numbers.
I haven't messed with the HS at all, it is all the way out atm. So, I'm sure those numbers will get higher as I mess with it. But I might just wait for my bottle conversion to get here before doing any tuning. No sense in tuning if I'm going to have to do it again in a week.
Did some quick tests. Hades is now shooting at 800fps. NSA 17.5gr is at 760fps. NSA 20.2gr is at 710fps. I am happy with these numbers.
I haven't messed with the HS at all, it is all the way out atm. So, I'm sure those numbers will get higher as I mess with it. But I might just wait for my bottle conversion to get here before doing any tuning. No sense in tuning if I'm going to have to do it again in a week.
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There is no need to degass your tank if you use the Huben Cricket Drop-block. There is a STOP grub on the bottle attachment collar that seals the bottle airflow from the block/regulator.
If you have a Gen lll Notos, you will have a degassing grub on the air-block to dump the regulator.
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Ok? I wasn't using a drill press.. so I'm not going to risk it. 4.5 was a tight fit with near zero play. Forgive me for assuming some thread material would be removed in the process.
Also not using that drop. I'm using the cricket inline regulator on a super well block. The huben drop block reg wait time for delivery was up to 8 weeks at best when I did this. The super well and cricket inline adjustable reg were next day delivery. So I did that. Degassing, then testing and repeating the issue isnt fun. It's a statement. Using the grub screw vs. Loosening the block pressure gauge doesn't take the process less tedious.
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There is no threading material removed, the actual opening is 4.5mm as measured with calipers.
Also, drilling to 4mm and using a hand reamer to 4.5mm is safer, cleaner and gives more laminar flow.
They are not expensive.
Also, drilling to 4mm and using a hand reamer to 4.5mm is safer, cleaner and gives more laminar flow.
They are not expensive.
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Doesn't matter, there are many others with the Notos that need accurate information and not just anecdotal experiences.
We all read and share information, if you post your experiences as fact and they are only experiential, then someone with the factual knowledge needs to step up and make sure that information is shared.
I've done hundreds of these conversions and have the right tools for porting. Let's try to make this thread a good resource for all.
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Bit harsh there Firewalker. I understand your trying to help and I appreciate your information. And I agree that it doesn't matter If he was asking for advice or not, the information is helpful to others. But your basically saying is that no ones thoughts matter and shouldn't say anything because they haven't done it as much as you.
I'm sure a 4.5mm works better but for me and others that don't have the tools or experience doing so, 4mm is a safer option. And, at least for me, works fine.
I'm sure a 4.5mm works better but for me and others that don't have the tools or experience doing so, 4mm is a safer option. And, at least for me, works fine.
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I would concur if the author had simply made a statement of opinion instead of continued claims of fact.
I certainly am not the only voice nor am I the only person who understands the facts in this case, It's also not my opinion but data that has been derived from several sources that one would consider experts.
I have the same freedom to opinions as others do to state my own opinion just as you are doing now.
Please don't mistake wanting to keep people safe and well informed with trying to be the know it all on the forum.
Bad information can lead to injury and/or death.
Let's try to state opinions and experience as such, please.
I certainly am not the only voice nor am I the only person who understands the facts in this case, It's also not my opinion but data that has been derived from several sources that one would consider experts.
I have the same freedom to opinions as others do to state my own opinion just as you are doing now.
Please don't mistake wanting to keep people safe and well informed with trying to be the know it all on the forum.
Bad information can lead to injury and/or death.
Let's try to state opinions and experience as such, please.
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I wonder if that's why I kept getting jammed slugs.
I ended up replacing that piece after dropping the barrel assembly, right after I cleared the jam with a dowel! Doh!
I wish I knew there was a newer option when I replaced mine. I guess I'll have to do it again. I just had another almost jam this morning...
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