Fx crown plenum

Rogvi can you please share the dimensions of your plenum for those of us who want to try to make one....also the type of steel? Thanks for that.

I have a crown but i have not yet try to make anything yet. 



i would like to know the plenums thread size please.

I suggest 416 stainless steel. once heat treated, that stuff can reach 90ksi yield easily. 

Plenum threads should be M18X1

Hello. I made my fx crown continuum 25 cal. Power plenum 13-15 cm3 steel with an adjustable valve spring.Hammer 10 g. At 150 bar. max speed with JSB MK II 984 fps and with NSA 33.5 gr. 971 fps. So far, that's enough for me. If you go more than 155 bars, you need 12 g. hammer. I have now started testing the new JSB KnockOut 33.49 gr. 951fps. The results are very good. With these settings I get 50 shots.

Hey Arunas,

Well done! I am surprised you also made a mini plenum because the bigger one should give you more than enough. Can you show more photos of your valve pin setup? It looks interesting. Does your pin go all the way to the other end where you can tension it like an Impact?

"I don't have a photo." In this way the valve pin goes to the other end where it is pressed by the spring same as fx compact

Just mounted a powerplenum on a Crown in 25 cal 600mm

And a hammer mod

Results is at 160 bar reg with the Jsb mk2 is pellet speed 292 ms (958fps) and with the kings 323ms (1060fps)

Click to expand...

Hi. I was wondering if you please could share the dimensions of your plenum?

It would be at great help for me and other people. 

Rogvi,

Do you make these plenums for other FX Crown owners.I think you are onto a good thing here with plenty of Crown owners putting their hands in their pockets willing to buy these off you.You have done an exceptional job if you dont mind me saying so.I cannot understand why FX or Huma hasn't started making them!

Rogvi,

Would you be interested in making one of your FX Crown plenums for me.I would like it to be as large as possible but not where I have to file away any of the trigger mechanism.Would it be possible to make it in stainless steel,if not brass would be fine.I think ypu are onto a winner here.Just let me know how I can pay you plus postage.

Hi Monaro,

I dont think that Rogvi will make them.

I had my Crown apart today installing the larger 6.3 mm valve seat and a stronger hammer spring.

I already tried to make a 3D drawing for a similar to Rogvi Plug.

I 3d printed it and it fit without problems. So now I have a drawing - Looking for some to make me one in steel.



If somebody could machine a handfull I think they would much needed.

I drilled my original plug out from ø12 to ø13 mm.

Togeher with the new Titanium ø6.3 mm valve, and a stronger hammer spring it gave me + 30 fps at 150 bar.

Now there is a lot more power if i raise the pressure to 160 bar, but I really would like to keep it at max 150 bar.

Now the Crown is shooting the JSB Knockouts .22 / 25,39 gr with 940 fps so not a major power increase .

I hope that the larger plenum plug will make it more on top of the job.

At least so I could keep the speed, while lowering the pressure a bit.

I have the 600 mm superlight superior standard barrel - and it is a laser with Knockout slugs out to 120 yards.

Further out it opens up the groups too much. So I hope the extra speed will keep them in tight groups - also further out.

Best regards from Denmark

Claus

Claus,

Would you be interested in making these plenums,I for one would buy one from you.Might be worth just seeing how many members would want to buy one from you.You might be onto something here to make some $$$$$$.All the best.

Can someone please help me.I noticed on a forum that someone was making a new FX Crown power wheel that had 14 positions I think.Can anyone let me know where I can buy 2 of these power wheels.

I would be interested in both plenum and power wheels!

monaro said:

Rogvi,

Do you make these plenums for other FX Crown owners.I think you are onto a good thing here with plenty of Crown owners putting their hands in their pockets willing to buy these off you.You have done an exceptional job if you dont mind me saying so.I cannot understand why FX or Huma hasn't started making them!

Click to expand...

Have you made one for the mk2. I have a .25 600mm Crown mk2 and would love to shoot 33.4 nsa at 970.