Larger plenum test on Impact X .30 700mm ... Test No Good See Edit

Interesting reading but growing frustration with where and how to get these parts. Now, apparently FXUSA is abandoning parts sales... isn’t that one reason they were set up to begin with? I’d like to get an enlarged TP from FX I’m not set up nor skilled enough to do myself Guess I can always try emailing them if they don’t then who?

I feel like a starving guy watching someone cook a steak!
 
To get maximum flow from the external plenum tube:

1. bore out gauge hole to M14X1.5 ----->75-100fps increase

2. need new plenum with M14 X 1.5 with 9mm bore hole 

3. valve housing need clear passage for the 14X1.5 bore ---see photo

4. the smallest air restriction are the transfer port on barrel and pellet probe, so dual port them see photo 45-65fps+ increase

FPS are actual testing---> no math !



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How does the M14x1.5 bore seal when using a sideshot magazine?
 
I just finished reading this entire post and agree wholeheartedly with Bob where he says it is, "hard to argue with real world results". Ernest always does things this way...he experiments with different ways of doing things until he hits upon the way that gives the best results. Ernest is not a physicist or mathematician but he does use the scientific method to get from where he is to where he wants to go.

I have learned almost everything I know about working on Wildcats, Streamlines, and Crowns from trial and error the same way...the times that I hit a brick wall and just can't figure out how to do something I call Ernest. He always laughs because I need him to "bail me out again" but he generously spends his time explaining a solution to the problem so that I can understand. Usually the answer was right in front of me but I just couldn't see it. 

My point is there is no better way of figuring out a problem than trial and error...in short order you find out what works and what don't. And the proof is in the results over the chronograph and down range on the target. Everything else is just a bunch of conjecture based on abstract thinking...and idle talk.
 
I agree that Mr Rowe's power tune works awesome but I can't purchase the parts to install myself and I don't want to ship my gun there to have the work done so I've got to make my own. Sealing an M14 hole with the sideshot magazine mount in place is my hangup. The only way that comes to mind is using two bonded washers with a spacer in between.
 
I agree that Mr Rowe's power tune works awesome but I can't purchase the parts to install myself and I don't want to ship my gun there to have the work done so I've got to make my own. Sealing an M14 hole with the sideshot magazine mount in place is my hangup. The only way that comes to mind is using two bonded washers with a spacer in between.

I used a thick delrin seal that has oring groove on oring on each side to seal the plenum tube.
 
Im still on 1/8 bsp with 6mm hile, made plenum about 22cc ( by calculation ). DImensions are : L70mm x Dia 35mm with 4mm wall thicknes that I believe can be less. The way I have seal it is with 3 o rings as shown in pics below AND IT WORKS PERFECT.

Also, the top part of plenum has step 22.5mm to tighten the biggest Oring. This is how its made and works without any additional parts.

And if you dont want to use plenum anymote ... put back manometer and no problem.

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Guys, regarding the sealing of external plenum, my humble recommendation is teflon tape without O-ring. I use teflon tape also to seal 1/8" BSP Foster couplers (running on 300 bars) and it works without problems. If the ext. plenum needs to be removed, so I take off the old teflon tape turns and apply new (usualy 15 turns, teflon tape I use is quite thin). Just be sure that teflon tape does not extend to inside of the gun.
 
Guys, regarding the sealing of external plenum, my humble recommendation is teflon tape without O-ring. I use teflon tape also to seal 1/8" BSP Foster couplers (running on 300 bars) and it works without problems. If the ext. plenum needs to be removed, so I take off the old teflon tape turns and apply new (usualy 15 turns, teflon tape I use is quite thin). Just be sure that teflon tape does not extend to inside of the gun.


Why put teflon tape on a bspp fitting that is designed to seal with an o-ring or bonded washer? I think your seal is actually happening on the teflon washer at the bottom of the hole.