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Drilling the .25 Transfer Port?

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Re: Drilling the .25 Transfer Port?

Postby Keith » Mon Sep 11, 2017 4:57 pm

Thanks for sharing your insight on my modifications .....I have heard of the TSS, but I'm unsure of what it actually does? Could you share the benefits of having this installed along with the other mods that I have already accomplished.
I do appreciate all the help that I am getting from you guys!!
K.
Keith
 
Posts: 12
Joined: Sat Oct 08, 2016 6:05 pm

Re: Drilling the .25 Transfer Port?

Postby 22synrodn » Tue Sep 12, 2017 12:30 pm

The TSS (Twin Spring System) uses two springs instead of one for easier cocking and more adjustability because both springs are adjustable. The end results would be the same as an SSG in that you can have a gap between the hammer and the valve to prevent hammer bounce or wasted air per shot. With the WAR Cobra valve this is not as critical as with a stock valve because the Cobra valve prevents hammer bounce by design somewhat, but I still use a TSS with a gap myself. You could also just install a short stiff spring strong enough to reach your desired power level and still keep a gap to prevent wasted air which would be the cheapest route.

The other mod I use is an MDS nylon hammer that weighs 55 grams. This lighter hammer is able to reduce the dwell time of the valve opening period and makes for a more efficient tune with a lower ES than when using a stock 78 gram hammer. I use a 12.5lb main spring and a custom 14.8lb inner spring in my TSS. The cocking is much harder than stock, but is doable to me. I will be switching over to the new balanced ART SS valve soon and my cocking should return back to near 6-10lb. stock cocking with it for the same 51 FPE power or more.

The other parts that are important is the amount of space or CCs you have on the regulated pressure side. That is why I use the Hill gauge port that has a lot more plenum space than a stock gauge port. Your Huma may have a built-in gauge port and the Hill gauge port may not be needed in your setup, idk. If you have a built-in gauge port you can add a spacer between the reg and valve to increase plenum, but that maybe a custom made part. Maybe the Lane regulator spacer would work? The more plenum space you have the more power you can create and the higher the reg set point the more power you can make. I set mine at 1975-2000 psi for my 51.5 FPE tune.

The bigger you go with the ports, the easier it will be to reach a power tune with doable cocking effort, but be very careful about opening your barrel port because if you go too wide the pellets will drop when passing and get cut on the edge of the port. I cut an oval shaped port to keep the width at .187 to prevent this. I am currently at .220 on the barrel port overall and the valve and TP are at .250. This is just food for thought on the ports and am not recommending this. It is up to you how far you go here. I only know of a couple of other guys that have gone this big on the barrel port and we are all experimenting.

This is all just general information on what I've done to my SynRod and there are a lot of topics about increasing power on the .25 cal. You just have to do some research on multiple forums, which is a lot of what I've done to reach my goals. A lot of talent out there.
Romans 8:1-11

22 Synrod Unregulated. Tuned using JSB 18.13gr:
30 Shots @ 31.02 FPE Avg., ES 1.36% (12 FPS), 1.58 FPE/CI


25 Synrod Regulated. Tuned using JSB MKIIs 33.95gr:
24 Shots @ 55.92 FPE Avg., ES 2.08% (18 FPS), 1.45 FPE/CI
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22synrodn
 
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Re: Drilling the .25 Transfer Port?

Postby Keith » Tue Sep 12, 2017 4:31 pm

22synrodn wrote:I say great job so far, but you are missing a lot of shots. You should be around 30 shots or more being just shy of 43 FPE. I have basically the same setup with Huma reg, Cobra valve, and opened ports getting 32 shots at 51.5 FPE. That is on a 3200 psi fill though, but still your shot count is low. I do have a TSS for wasted air. Just saying there is more in there.


I have heard of the TSS, but do not really understand what it is and what the advantages are of having it......could you give me some more understanding of this mod and whether or not it would be a justifiable addition to the mods that I have already accomplished?
Again your input is appreciated!!
Keith
Keith
 
Posts: 12
Joined: Sat Oct 08, 2016 6:05 pm

Re: Drilling the .25 Transfer Port?

Postby 22synrodn » Tue Sep 12, 2017 8:41 pm

Keith wrote:
22synrodn wrote:I say great job so far, but you are missing a lot of shots. You should be around 30 shots or more being just shy of 43 FPE. I have basically the same setup with Huma reg, Cobra valve, and opened ports getting 32 shots at 51.5 FPE. That is on a 3200 psi fill though, but still your shot count is low. I do have a TSS for wasted air. Just saying there is more in there.


I have heard of the TSS, but do not really understand what it is and what the advantages are of having it......could you give me some more understanding of this mod and whether or not it would be a justifiable addition to the mods that I have already accomplished?
Again your input is appreciated!!
Keith


Here is the video of the TSS from the maker https://www.youtube.com/watch?v=qQ2u04aWSi8.

You can also contact him (Travis) for more info:

http://www.airrifletechnology.com / Contact [email protected] or call (661)904-7046
Romans 8:1-11

22 Synrod Unregulated. Tuned using JSB 18.13gr:
30 Shots @ 31.02 FPE Avg., ES 1.36% (12 FPS), 1.58 FPE/CI


25 Synrod Regulated. Tuned using JSB MKIIs 33.95gr:
24 Shots @ 55.92 FPE Avg., ES 2.08% (18 FPS), 1.45 FPE/CI
User avatar
22synrodn
 
Posts: 1134
Joined: Sat Jan 10, 2015 4:33 pm

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