Plenum home made for Crown

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The plenum for my Crown. 25 is finally ready, but not yet in my possession ..... the courier should arrive in days to deliver it to me.
 
Total length 80mm. Diameter 25 mm Wall thickness of the cylinder 3 mm.

Possibility, if needed, to mount the pressure gauge to measure the pressure inside the plenum. The plenum will be mounted in place of the regulated air pressure gauge.

How will the plenum, aesthetically, mounted on the Crown, I don't know, but it certainly won't be nice. But the "operation" is totally non-invasive, in a few seconds the pre-chamber can be removed, so if I don't get appreciable advantages at the level of power and precision in the long range and / or at the aesthetic level it will be a monstrosity, I will report the crown as the FX built it.
 
I am interested in how it works out for you . I was going to try making one as this one posted a while back but your limited to the length by the trigger. You might be able to get another 3/8” if you trim off the front of the trigger bar . In your design you could make it a little wider to add volume if needed. The guy who posted this one never followed up to let us know how it worked out. 
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Yes @Yo, my pre-chamber will be very similar to the home made plenum mounted on the Raw that was published on the forum a few days ago. Aesthetically, the plemun of the RAW is more "balanced", for the reason that it is shorter and, it seems, at least from photos, more beautiful aesthetically. On the other hand, but only the tests will tell, my prechamber is longer and more capacious so, theoretically, I could have some more advantages. My advantage is that I started with the works for the construction of a new custom stock for my crown, so I hope to be able to integrate this cylinder well into the aesthetics of the "new crown".

@vmaxpro ... no, it is unique specimen. I only had one built and yes, whoever did it, tested it at a pressure higher than the operating pressure. The craftsman who made me the prechamber has been working on PCPs for a long time, has experience in high pressure, so his product is trusted. However, I asked him for more specifications on the test pressure and the type of aluminum used .... I'll let you know the details.
 
@leatherman, with my "Home made plenum for Crown" project, I initially started with the idea of ​​building something slightly invasive and visible, so I had two different types of steel plemuns built, similar to those who built the user of the Danish islands. But their capacity is very limited, 2 cc maximum, so I started with the second phase of my little dream, namely the cylinder pre-chamber. I will do all the necessary tests, also combining the small plenum with the cylinder one and then I will see if "sacrificing" the beautiful crown line is worth it or already the small plenum (Danish model) is sufficient for my goal. However, I have not filed the trigger block base, so the small prechamber is even less capacious. I take some pictures and then publish them.
 
"SPARAI PERSONALMENTE L'INFERNO CHE AVVIAMENTO (SOLO AZIONE) DA UN BUON RESTO O VISTA SOPRA GLI OBIETTIVI CRONICI E LUNGHI SOLO PER RENDERE DAMN DIRITTO SICURO CHE FUNZIONA PRIMA DI EFFETTUARE IL CALCOLO!"



@Yo, forgive me, but I have not understood anything of what you have written .... I am an Italian user and I find it very difficult to write my messages and to translate those of other users, so you could rewrite your message. Thanks and sorry again.
 
Just a thought! Why wouldn't a short filter that is MT. There good for 4500# but are the threads correct? Cheap and come in colors. Threaded on both ends. Just went and measured and the hole gauge hole is 1" and the filter is 1.25", so would need the cut the hole. Length seems big enough for a good size plenum.

I tried that. Only added a few fps to my Crown. As a way to test various things attached to the reg gauge hole, I screwed the BSP threaded QC fitting that comes with the Crown into the reg gauge hole. With that, anything with a male QC fitting can be attached. Like a inline filter with a male QC fitting on one end, and a gauge on the other. Also useful for temporarily attaching a larger more accurate gauge for tuning...

Picture of when I've had just a small Huma gauge installed.

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No, I never thought of measuring the volume of the regulator housing, but since the crown is totally disassembled, before reassembling it, I can measure it. The volume of the plenum is 19.5 cc, which together with the volume of the small "Danish style" pnenum, brings me the total volume of air set at around 22 cc.

The Italian post offices are very slow, unfortunately, and the cylinder has not yet arrived.