Benjamin Gunnar listed on PA now.

Let´s take the last Q first.
Short reply is that if you want to keep it within realms you could use the reg pressure gauge for entry port, it just needs to be enlarged somewhat at the seal for use as entry. Gauge port is on thread M10*1mm
Me, i´m always conservative as *ell when it comes to pressure vessels in as much that i basically use steel only, and then high pressure steel tubing. Ie; stuff made for the task at hand.
Yes. I´m more than capable of making the pts needed out of aluminium, it´s just.. suspenders n belt. Point being that aluminium has a finite life while correctly designed steel does not (this is defined as 10 million cycles).
In short i use steel as that way i´ll most likely never have someone walk up to me down the line to tell that one of my plenums didn´t make it and that there´s bodily harm involved.
Silly? Call me whatever.. that´s just me.

That being said i guess most pressure vessels you´ll run into ARE out of aluminium. As such i´d say 6086 or 7075 (both as T651) is what to go for. Know many of the chinese mans use 6082, which i honestly feel is so-so at best and that being said knowing all to well that there´s TONS of such bottles and what not on the market that works perfectly fine.

What many fail to realize is that the entity of a plenum can be regarded in many more ways than one and often times the volume arrived on is therefore a matter of personal prefs. So called standing waves and what not CAN come into play and god knows what more..

Having established that rambling.. for a 100J gun go for something along 60-70cc´s for starters i´d say. Seeing that the stock "plenum" on the NYX/Gunnar is hoovering around 20cc´s (if memory serves, did the math but it´s been a while..) anything added will sure help.
There´s those claiming that 10cc´s will support 10fpe and then there´s those claiming that every 10cc´s will support 20fpe.
Me i´m of a different notion and having done the math the truth as i regard it is that the curve we´re talking about is logarithmic to sense. Thus, the more power we´re to extract the larger the plenum needs to be, and that NOT in a linear fashion.
None the less. A rather reasonable 60-70cc´s should get you well under ways and most likely satisfy your power hunger, and then some.

Using the reg pressure port (underneath the gun/main block) might look a tad off but truth be told it´s by FAR the easiest way "in" for the novice. Point being that the diameter and the threads used will take the abuse, within limits of course, why as long as you protect said plenum from absolute mayhem as far as external force you´ll be just fine.

Spring then.
Here i believe MANY cross the bridge for water cause as been touched on in the current Notos thread you can sure get lost on this one... and no matter if you do the math the real question is if you´re really all that much for the wiser.
Me i´m an engineer and that crap is sorts of "engineer 101" together with doing the math for pressure vessels and so forth. Doesn´t help more than point the right direction as the issue in itself can be rather complex.
Thus.
For the novice i´d say look springs up based on wire diameter, outer diameter of spring and No of coils vs length. Don´t bother getting into so called K values and what have you, just as a piece of friendly advice.
However.
That means that springs by NO measure have to be something "pcp specific" as there really is no such thing. Get the stocker out of the gun and bring that with you for your local hardware store to see what they can come up with. Try the thing-s for size.
Chrono never lies and nor does consumption of air.

That said please be aware that there´s no such thing as free lunch. Granted, the NYX/Gunnar sports a 500cc bottle but no matter as... as power goes up you will consume more air and at a certain point will run into a shot count that simply ain´t acceptable to YOU.
Sure.
Hammer bounce and so forth sure doesn´t help, but again.. as long as not "dead locked" a matter that carries an absolute array of amounts of evil.
But by all means, read up on hammer bounce and its effects. That´s just healthy seeing what you ask.
Believe there´s even sorts of tutorial vids on YT on the matter. Just be aware that there´s very, not so say extremely, little that´s either black or white as far as this. Most of it is different shades of grey ;)
 
I wanted the Reximex Throne G2 version with the three barrel option but Crosman has nixed that with the Gunnar in the USA. Must be a way to puchase the original Reximex Throne from overseas.




Give that a second thought.
The Throne, both versions, sure lacks plenum volume as well

68.jpg


Unit sports what Reximex call a "pre-chamber" stock, but that thing is like the original plenum on the Impact, along 20+cc´s and that sure won´t cope.
So as you can see in the picture i enlarged that with one by me out of steel that´s on approx 100+cc´s, which sure did the trick.
However...

1.jpg


Reximex is as far as i´m concerned a Turkish manufacturer on the move. Their latest designs the NYX per above and in turn this.
The Meta Premium. Comes in that roller flight case you see in the picture. The thing is that the Meta Premium is an upscale piece of kit vs the Throne it isn´t even funny and no doubt build quality as well as material choice and design is right up there. Just, still with a very reasonable hang tag (about half of what an Impact will run you)
It carries loads of features, some to expect and some not.
It sports a 90cc plenum stock. A 700mm barrel. 480cc tube (when aluminium, they offer carbon fibre ones too) and what not.

41.jpg


In turn this anti bounch device... wicked!
What it does NOT is sport transfer ports enough to really make the thing haul, this is where YOU the end user come in.

29.jpg


Mine there is a 25cal right so when drilling the transfers out what i didn´t account for was "breaking into water" (cutting into another hole).
Well. I did.
As it turned out there´s a small hole for a spring and detent for the mag and as i went past 6mm by any margin for the transfer i broke into that hole and couldn´t for the LIFE of me figure out where that leak was at that made the rifle loud, down on power and so on.
Well. Right there.
Remedy was REAL simple. I threaded and shoved an allen stoppie down that hole set with Loctite and then, as can be seen, yet another allen stoppie at the end of said hole.
Presto.

Where this unit is at it´s tossing the max length 25s the mags will take, which is 42 grains, at an easy 1050-1070. It´s currently setup "stffer" than my M3 even, and sure hands the M3 a run for the money no doubt.

Caveat to the Meta is that you´ll have to enlarge the transfers yourself. Stock they´re on something like 4 mills, and that´s not even CLOSE to what the design will take. Put the suggestion to Reximex why not just set a "performance online shop" up where they for instance offer main blocks so modified. No doubt there´s money to them in that too.

Since i´ve talked the situation over with Reximex (the lack of mag depth - for even heavier fudder) but as of current do not know where they´re at on this. Again.... an aftermarket main block is called for
See. The point here is that Rex and Kral are under the same owners right and it just so happens that the Kral mags are absolute deadringers for the Rex ones. In other words all that´s needed is for Rex to walk across the yard and ask Kral for their mags and then change ONE measurement on the CNC that makes the main blocks and we´d be there so to say.
On my own there in the pictures, as i keep heavy machinery i´m giving thought to just picking 2 or 3 Kral mags up and set the main block on the mill of mine and be done with it already.

None the less. The Meta Premium is an absolute *rapload of gun for the money.
Sans flaws then?
No. Of course not, but the thing is they can all be handled - which is more than can be said for many many other pcp´s out there.
 
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Thank you for sharing your experience with us, Mr. Racing. The Reximex brand has not penetrated the U.S. market yet, so there is little first-hand knowledge to be shared. I feel my Tormenta is lacking a bit in stock form for a .25 cal. My unregulated gun runs from 205 bar to 200 bar - then it falls off the cliff. I do get about 40 shots within reason and that is perfect for my pest control efforts. 4 full mag and a full load of air = about 2-3 hours of pest control.

I am pretty comfortable with the Kral designs, but have not done much exploratory surgery on the Rex, yet. Thanks again for posting about your findings.
 
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Give that a second thought.
The Throne, both versions, sure lacks plenum volume as well

68.jpg


Unit sports what Reximex call a "pre-chamber" stock, but that thing is like the original plenum on the Impact, along 20+cc´s and that sure won´t cope.
So as you can see in the picture i enlarged that with one by me out of steel that´s on approx 100+cc´s, which sure did the trick.
However...

1.jpg


Reximex is as far as i´m concerned a Turkish manufacturer on the move. Their latest designs the NYX per above and in turn this.
The Meta Premium. Comes in that roller flight case you see in the picture. The thing is that the Meta Premium is an upscale piece of kit vs the Throne it isn´t even funny and no doubt build quality as well as material choice and design is right up there. Just, still with a very reasonable hang tag (about half of what an Impact will run you)
It carries loads of features, some to expect and some not.
It sports a 90cc plenum stock. A 700mm barrel. 480cc tube (when aluminium, they offer carbon fibre ones too) and what not.

41.jpg


In turn this anti bounch device... wicked!
What it does NOT is sport transfer ports enough to really make the thing haul, this is where YOU the end user come in.

29.jpg


Mine there is a 25cal right so when drilling the transfers out what i didn´t account for was "breaking into water" (cutting into another hole).
Well. I did.
As it turned out there´s a small hole for a spring and detent for the mag and as i went past 6mm by any margin for the transfer i broke into that hole and couldn´t for the LIFE of me figure out where that leak was at that made the rifle loud, down on power and so on.
Well. Right there.
Remedy was REAL simple. I threaded and shoved an allen stoppie down that hole set with Loctite and then, as can be seen, yet another allen stoppie at the end of said hole.
Presto.

Where this unit is at it´s tossing the max length 25s the mags will take, which is 42 grains, at an easy 1050-1070. It´s currently setup "stffer" than my M3 even, and sure hands the M3 a run for the money no doubt.

Caveat to the Meta is that you´ll have to enlarge the transfers yourself. Stock they´re on something like 4 mills, and that´s not even CLOSE to what the design will take. Put the suggestion to Reximex why not just set a "performance online shop" up where they for instance offer main blocks so modified. No doubt there´s money to them in that too.

Since i´ve talked the situation over with Reximex (the lack of mag depth - for even heavier fudder) but as of current do not know where they´re at on this. Again.... an aftermarket main block is called for
See. The point here is that Rex and Kral are under the same owners right and it just so happens that the Kral mags are absolute deadringers for the Rex ones. In other words all that´s needed is for Rex to walk across the yard and ask Kral for their mags and then change ONE measurement on the CNC that makes the main blocks and we´d be there so to say.
On my own there in the pictures, as i keep heavy machinery i´m giving thought to just picking 2 or 3 Kral mags up and set the main block on the mill of mine and be done with it already.

None the less. The Meta Premium is an absolute *rapload of gun for the money.
Sans flaws then?
No. Of course not, but the thing is they can all be handled - which is more than can be said for many many other pcp´s out there.
So far I took your advice and I added a slightly smaller diameter spring into my stock hammer spring. I could tell right away that fps was up and also I have a very good suspicion that now the valve open for a tad longer when I take a shot. Very noticeable difference! I haven't gone any further yet, but I do enjoyed shooting a stronger gun all weekend. Thanks again racing!