My Edgun lost some velocity
Actually a lot. Almost 300 fps according to my chrony. I was worried because it sounded anemic and ran her through the chrony. It’s shooting at 600 fps with .25 cal jsbs. It was shooting at a steady 900 fps before. I checked the breech probe seals by placing a piece of tissue over the loading port and it did not indicate any blow by. I’m at a loss. I open to suggestions.
Thanks,
Gabe G.
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Hi Guys,
I think I figured it out. After checking all the things you guys mentioned, it was the HST screw. I didn’t suspect the HST screw because it was locked by the small set screw. Evidently it was not doing its job. I remove the HS by unscrewing the HST screw to inspect the spring and check if I had the same issue as Tacoma Tom. Everything looked fine. I was at my wits end. I didn’t mark the screw when I removed it so I just screwed it in. I guess where it should be and ran a shot over the chrony. It read 760 fps. I turned it in one turn and the velocity increase to 879 fps. I was close to my original velocity of 900-910 fPs. A smile came across my face 🙂 I tunned it in a little more and wound up at 917 fps at 180 bar. The sun went down and I stopped adjusting the screw. I was happy to finally find out the problem but was perplexed why it moved in the first place. Yesterday I checked the HST screw and swore it was well secured. I doesn’t matter now. I’m thinking of locking the HST with a jam nut once I do my final adjustments tomorrow. Anyways, thanks for all your help and I’m glad it was not something too serious. I was also a good learning experience. I understand how my gun works better and the experience was worth it.
thanks again,
Gabe G.
Thanks guys!
I will use your suggestions to guide me.
I will report my findings.
I checked the hst screw and hs and they looked ok.
I’ll double check and also look at the brass guide on the valve body.
Gabe g
To help you out a little more, – here’s how the brass bolt looks (middle of the picture) when turned in fully:
Good luck !!! 😀
I agree with Zoco,
Check your hammer spring set up. When mine went bad it made a big fps difference and sounded very strange.
The hammer spring retaining rod stripped out of its threads and was hanging around loose. It was hard to see at first. There’s some pics in my thread “Finally got my parts from Tony :D” Look there to see what I’m talking about.
Good luck!
I don’t think that you have broken an air valve rod. I have broken a few and when they break, the valve’s sealing face won’t seal properly and the air tube’s pressure will vent out of the barrel. If you break one, you can’t shoot the gun until the air valve is replaced.
The hammer spring could be broken, I doubt that it is.
If the R3 has a full charge of air, I can only think of 3 things that could happen to cause a 300 fps loss.
The regulator’s pressure setting lock screw has come loose and the pressure setting screw has loosened allowing you set pressure to drop. I doubt that has happened.
The hammer spring tension adjusting screw has loosened; I think that has probably happened.
The hammer end of the air valve rod slides thru a brass bolt. The brass bolt screws into the rear end of the air valve housing and supports the air valve rod. When the gun is fired, the hammer knocks the air valve rod in and the air pressure is released into the transfer port and pushes the pellet down the barrel.
The hammer’s face pushes the air valve rod in until the hammer hits the face of the brass bolt. I had a couple of PMs and phone conversations with a guy that had his R2.5, 25 cal long lose around 300 fps also. I couldn’t figure out what his problem was. Everything that I had him check was as it should be. He didn’t want to take the gun apart to check the reg so, he sent me his gun to see if I could find his problem.
It turned out that his brass bolt had unscrewed a couple of turns and the hammer couldn’t open the air valve rod enough to let the full charge of air out of the air valve housing and into the transfer port. I have never seen or heard of that happening before.
If your HST screw hasn’t loosened, you might want to check that brass bolt. To do that, you will need to cock the Matador, close the bolt, take out the 2 screws in the rear breech block and slide the block off rearward. You will then be able to look down into the gun and see if the bolt has unscrewed some. The head of the bolt should be tight against the aluminum air valve housing. If it has come loose, be very careful when you tighten it up, that bolt is pretty thin and I don’t think it would take much to break it.
Let us know what you find out.
If the gun has been filled, it sounds like your valve is not functioning properly….
Has the hammerspring adjuster come loose and turned itself out a little ?
Is the spring itself ok ?
Valve rod broken ?
From the top of my head……..
Cheers and good luck from Norway 😀
LOL. I was gonna post the same question earlier, but Hoot doesn’t have that little voice that tells him not to.
😆
Did you refill it after your last 60 shot string?
Sometimes it’s the obvious that escapes us.
No need for thanks!
Uncle H 😯 😯 T
PS: Put some soapy water around your fill probe and air gauge…the two most likely leak sites.
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Good to know it’s been sorted…….. 😀
For those who don’t know, (others skip reading) – this “silvery” screw is the hammerspring tension adjuster:
The little screw (comes in different versions) “on top of” the threaded part is supposed to lock the hst-adjuster. If that screw comes loose, – the silvery hst-adjuster may rotate itself out little by little. And it does not take more than a fraction of a turn of this adjuster before the fps of the gun “goes bananas”…..
Thanks Gabe for bringing this up…. 😀