I apologize, Marko...the stock 13" barrel was replaced with a 28" one. Supposedly this new barrel makes it very accurate and increases the FPS. When I first got the Sniper, it was shooting 696, 690, and 686 for the first three shots. With the new barrel and port work, its achieving around 810 FPS. I can't help but wonder if a few more foot pounds can be squeezed out of it.
Quote from: VaporTrail on October 08, 2022, 04:14:48 AMI apologize, Marko...the stock 13" barrel was replaced with a 28" one. Supposedly this new barrel makes it very accurate and increases the FPS. When I first got the Sniper, it was shooting 696, 690, and 686 for the first three shots. With the new barrel and port work, its achieving around 810 FPS. I can't help but wonder if a few more foot pounds can be squeezed out of it. There's 200-300 fps more to be had with 28" barrel and pellets, which actually means you should use heavier bullets if you want to go that high in power. I was pushing 125 grain bullets at 870 fps with only 21" .35 barrel from my Sniper X2, with 28" barrel that would have been around 940fps and 245 fpe (assuming 10fps/inch).
Quote from: rkr on October 08, 2022, 08:27:47 AMQuote from: VaporTrail on October 08, 2022, 04:14:48 AMI apologize, Marko...the stock 13" barrel was replaced with a 28" one. Supposedly this new barrel makes it very accurate and increases the FPS. When I first got the Sniper, it was shooting 696, 690, and 686 for the first three shots. With the new barrel and port work, its achieving around 810 FPS. I can't help but wonder if a few more foot pounds can be squeezed out of it. There's 200-300 fps more to be had with 28" barrel and pellets, which actually means you should use heavier bullets if you want to go that high in power. I was pushing 125 grain bullets at 870 fps with only 21" .35 barrel from my Sniper X2, with 28" barrel that would have been around 940fps and 245 fpe (assuming 10fps/inch).Ah...I knew there was a little more juice in the old girl. Rkr, at what fill pressure were you getting those numbers? Was that with 200BAR? Brian did mention that with the way the ports were set up, it limited him on how much he could bore out. In all honesty, I'd be happy if it shot at 884FPS with an 81gr JSB. Those power figures worked out just fine for me when I had the Winchester. Holy smokes. Over 1000FPS can still be available?
Oh nice. I think I'll be able to drill that out without goofing it up. Maybe that will be the piece of the puzzle that allows me to get a little more power. I'll keep the fill pressure to 200BAR and then adjust hammer spring to get my 140FPE. Uh...speaking of hammer spring adjustment; how exactly do I do that?
Quote from: VaporTrail on October 09, 2022, 03:17:56 AMOh nice. I think I'll be able to drill that out without goofing it up. Maybe that will be the piece of the puzzle that allows me to get a little more power. I'll keep the fill pressure to 200BAR and then adjust hammer spring to get my 140FPE. Uh...speaking of hammer spring adjustment; how exactly do I do that? You remove that L profile aluminium piece at the end of the breech and remove the locking mechanism for the skeleton stock (the button screws off but IIRC you need to take the grip off as well). That reveals the RVA that you can turn in or out. Mind you the hammer is rather heavy and the spring is soft so RVA may not have much effect on power. Using a stiffer spring does the trick.
The rifle is finally on its way back to me. Final numbers are 810FPS with 81gr pellets. Fill pressure recommended was 3000-3200psi and to fill slowly. Initial conversation on the phone I was told they could squeeze out at least 280FPE, but it looks like they fell a little short. I'll drop a performance review when I get the rifle and put some rounds through it. All I know at this point is that they did some hammer work, some transfer port work and possibly some valve work. The original 13" barrel was replaced with a 28" one, and that supposedly has made it very accurate. My biggest gripe with this entire process is the lack of communication; after that is the amount of time that it took. I don't mind waiting a little longer, but at least update me and keep a steady flow of communication going. I had three updates in the entire 2 months that the rifle was out there. Grand total spent? $659; that's shipping from me to them, tuning, and then shipment from them out to me.
Quote from: VaporTrail on October 19, 2022, 03:51:37 AMThe rifle is finally on its way back to me. Final numbers are 810FPS with 81gr pellets. Fill pressure recommended was 3000-3200psi and to fill slowly. Initial conversation on the phone I was told they could squeeze out at least 280FPE, but it looks like they fell a little short. I'll drop a performance review when I get the rifle and put some rounds through it. All I know at this point is that they did some hammer work, some transfer port work and possibly some valve work. The original 13" barrel was replaced with a 28" one, and that supposedly has made it very accurate. My biggest gripe with this entire process is the lack of communication; after that is the amount of time that it took. I don't mind waiting a little longer, but at least update me and keep a steady flow of communication going. I had three updates in the entire 2 months that the rifle was out there. Grand total spent? $659; that's shipping from me to them, tuning, and then shipment from them out to me. Huh, 810 fps with 81 grains is 118 fpe - that's less than Evanix RS2 version factory bottle guns do with 21" barrels (they were hitting close to 150 fpe in .35 with just RVA turned in). I would be rather disappointed with that result. My guess is they left that bottle connector with tiny holes in it causing awful restriction in the air path.
Found it, this is the bottle connector inside my gun. It was fully "modified" by the previous owner and I just smoothed out the edges and worst dents and left it as it was. Surprisingly it works rather well. You can see the small hole at the bottom, there were six of those feeding the valve in the stock gun. The connector is drilled out to 9mm both inside and the angled hole according to my notes. The tunnel feeding the valve chamber is also bored out to 9mm. This mod is enough to allow 210 fpe with 21" barrel so you should be able to reach 240 fpe with your 28" barrel.BTW, if someone knows where I can buy such male/male M18x1.5 threaded connector let me know - I would rather like to replace it.bottle-connector by abbababbaccc, on Flickr
I also forgot to mention that he put an oring on the probe instead of machining a groove inside the barrel for the oring. He said it would seal much better that way.
Quote from: VaporTrail on October 19, 2022, 06:06:38 AMI also forgot to mention that he put an oring on the probe instead of machining a groove inside the barrel for the oring. He said it would seal much better that way. He's right about the o-ring, it's better on the probe. Much easier to inspect and change and it eliminates the thin steel lip in between the barrel port and o-ring groove which always got me a bit worried. It also helps in feeding the bullets in parallel to the bore in to the leade in. It may wear a bit more as it travels through the magazine but as it is so easy to change it really doesn't matter.
Sorry to hear this Paul. 810 with a 28" barrel? I wouldn't be happy either. I have a bottle armada carbine with a 17" barrel and if my chrony is right it shoots the pellets from 900-850 over 5 shots. Hopefully you are able to open it up and get your velocities up where you want.
Things will work out for you once the airways get opened up. You should be able to get it into the mid 900's . I haven't shot anything with mine yet just paper and plinking. I have been shooting the FX hybrid slugs in mine and have been pretty impressed.