Fx crown plenum
- Thread starter Rogvi
- Start date
Hi Rogvi,
Have you got a sketch with measures for your increased plenum plug. It would be a great help please..
Best regards Claus
Have you got a sketch with measures for your increased plenum plug. It would be a great help please..
Best regards Claus
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Copying Rogvi's idea, which was brilliant for me, I ordered a small stainless steel plenum from a good metalworker, but I don't want to file the trigger, so he will do it to me with a smaller capacity. For this weekend, he should hand it over to me.
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@ Rogogi, no problem. Now I have the crown completely dismantled as I have to mount the new pieces: the 6.25 mm VS, the Huma double hole TP, the modified ammunition pusher and a hammer of about 8 gr. With all these changes and the plenum like yours, I hope you get power .... now I'm at 65J with 2.2 gr JSB King Heavy. The crown is a cal. 25.
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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)
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)
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Same reg pressure before 160bar all standard
I was getting 268 ms (879fps) with the mk 2
So 24 ms (79fps)more.
I was getting 268 ms (879fps) with the mk 2
So 24 ms (79fps)more.
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@Rogvi, is the power plenum one of the ones you made, or the one in the photos? What weight does the custom hammer you added? I withdrew my plenum, but they did it with the bottom too thin ... 2 mm. I'm afraid it won't keep 150/160 bars. I'll get a new one. Of course you got power with just 2 cc of pre-chamber more !!!!
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Rogvi is your gun .25 or .22 and what is the length of your barrel? My .25 is ahooting at 94 joules at 160 bar in .25 cal with 33.95 gr heavies and 700mm barrel without the plenum. I have ported and added heavier hammer and that is all.
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Rogvi i just saw above where you said it is a .25 with 600mm barrel. Nice! So you are getting the same as me but with a barrel that is 100mm shorter.
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I have made them both brass and steel.
Hammer weight is 8 gram
It is easier to get more power out of a 30 cal
There i only added the plenum and no extra.
This is the first 25 cal i made.
But with the plenum added you get more power out of it in low reg pressure.
Hammer weight is 8 gram
It is easier to get more power out of a 30 cal
There i only added the plenum and no extra.
This is the first 25 cal i made.
But with the plenum added you get more power out of it in low reg pressure.
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RabbitBlaster
I took the the 700mm barrel in 25 cal from the Impact and put it on the crown
Now iam getting 300ms (985fps)with the mk2
But it is to long
Like it more with 600mm
I took the the 700mm barrel in 25 cal from the Impact and put it on the crown
Now iam getting 300ms (985fps)with the mk2
But it is to long
Like it more with 600mm
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RabbitBlaster
I took the the 700mm barrel in 25 cal from the Impact and put it on the crown
Now iam getting 300ms (985fps)with the mk2
But it is to long
Like it more with 600mm
Excellent results Rogvi
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