De-tuning Edgun R3 to 12ft/lb, findings
So its obvious from what I have read and found the R3 is well and truly what we would call a FAC gun (Firearms Certificate) as such should be poor at sub 12ft/lb
Well I can confirm it is, my standard R3 with the HST turned down to give <12ft/lb gives about 100 shots from 230-130Barg, a spread of 10 to 20 fps with JSB Jumbo (15.9g) and even more of a spread with JSB Express and even more with the JSB RS, Jumbos shooting 15-20mm groups (with some flyers) at 30 yards
So read up on here and decided to follow the sage advice and have lowered the regulator to “1230” (which seems to give around 90Barg) and I have ported the transfer port down to 3.0mm with a 15mm long port adaptor
Now getting a quieter gun, 150 shots from 200-100Barg, a spread of 5fps with Jumbos, 7fps with express and 8fps with RS, Jumbos grouping <10mm at 30 yards, much worse with lighter pellets, couldnt hit shit before mods, can hit shit now but it has to be big shit 😀
So here is how I emptied the air (engineers vice as spreader), the regulator position (1230) and the port adapter from virgin PTFE
https://picasaweb.google.com/lh/photo/wMjxed3wKulDkJUQw6pKEMFbXz_tavukzAeWh6j-LtU?feat=directlink
https://picasaweb.google.com/lh/photo/KPC90NmWQS-RWdIgeloa08FbXz_tavukzAeWh6j-LtU?feat=directlink
https://picasaweb.google.com/lh/photo/A6HPKYVUG-XYMJPlsR66jMFbXz_tavukzAeWh6j-LtU?feat=directlink
https://picasaweb.google.com/lh/photo/c-2PLH3II-_r9Q1scnBNncFbXz_tavukzAeWh6j-LtU?feat=directlink
https://picasaweb.google.com/lh/photo/rjwEwTRohyrR9EIAnbsBuMFbXz_tavukzAeWh6j-LtU?feat=directlink
Minor point, I was surprised at the valve stem only sealing due to a “good fit” in the brass carrier – no seal
Would like to know more about the effect of reducing the void where the regulated air sits after it has passed through the regulator awating delivery to the transfer port via the valve, Bigtoe in a previous thread mentioned reducing this void to make the regulator cycle better – can anyone ellaborate on this?
I enjoyed stripping and tinkering with the gun and want to do more, but have to say shooting strings across a chrony is boring
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Viewing 5 replies - 1 through 5 (of 5 total)
Steeldreams – thanks for the photos, I have so many different accounts for different things, just cannot be bothered opening another one 😳
Synopsys – thanks for the comments 😀
210 shots!!! 😯
Nice spread too!
Great post!!!!!!!!!! :thumb:
I have a true Made in the USA rifle that gets 100+ shots (18fpe in 177) with a start pressure of 1600psi and an end pressure of 1300psi. Not as unrefined as you may think… 😉 😀
here are the photos in the above post:
So I have finished messing (for now) and have a completely different Matador – well in character at least.
Just lowering the regulator setting made a little difference, reducing the transfer port size made a little more difference, but reducing the volume of the exhaust chamber made a huge difference.
Just chronied a string from 200Barg down to 80Barg and got a very usable 210 shots – two hundred and ten 😯
Chose 200Barg top pressure as I think this is what the manual I have says, its in Russian but the fill section has refernce to “200 ATM” so I think this is top pressure, if I filled higher I may get another 20 shots 😯
The gun is now far less harsh to shoot and much quieter – its now a Russian made but refined European machine not a brash American unrefined one 😛
The strings prior to reducing the exhaust chamber were around a 15-20 FPS spread, this last 210 shot string had a spread of 7 FPS and a SD of 2 😯 😎
There was a little deviation in consistancy around 90Barg so I will probably use from 200>100 for simplicity.
The pressure “usage” was typical, i.e. less shots per Bar at the top of the curve than at the bottom.
The only downside is all this is at an average 11.3 ft/lb not 30 😥
Below is the sleeves I made to reduce the exhaust chamber, now the maths to decide how much to reduce it was simple, I was initially getting around twice the shots the standard R3 is quoted as giving so in order to get the regulator cycling every shot I halved the volume:
https://picasaweb.google.com/lh/photo/K7ucapbCKH1BNbbFNdNks8FbXz_tavukzAeWh6j-LtU?feat=directlink
https://picasaweb.google.com/lh/photo/tGxUj9fsiPr5hf-QH3TPKMFbXz_tavukzAeWh6j-LtU?feat=directlink
https://picasaweb.google.com/lh/photo/cIEeDD7V5u_7hbK5lEv6uMFbXz_tavukzAeWh6j-LtU?feat=directlink
As can be seen on the photos the sleeves have a step in them this is allow air to flow from one side of the chamber to the other through the two offset holes.
One interesting thing is the divider in the chamber is not central, its 2mm offset which means if you fit it the wrong way round the valve spring is compressed by an extra 2mm and much harder to compress – one to remember when re-assembling.
I think the final thing I am going to look at is some acoustic material around the hammer chamber to quieten it even more 😎
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Synopsys – thanks for the comments 😀
You are welcome Lol Moore.. those are excellent photos.