Ultra budget PCP, the Kayoba PS .177" cal

[Racing]

First up.
Sry about this post being split over days.
This is mainly as i use Pixlr to reformat pictures to more forum friendly proportions and Pixlr has since a while back arrived on that those of us that use their service are limited to 3 pics a day..
So sorry about that.. it is what it is.


Super ultra budget PCP´s on the agenda then!
Is there such a thing? Well, evidently. I guess we all know that we can get them type of guns on Amazon and what not but truth be told.. kind of a crap game if what arrives is a gun, a plastic toy or a brick.
So what about super ultra budget PCP guns that can be store bought then? That you can physically fondle before you hand your hard earned cash over.
Is there SUCH a thing?

Yes.
Yes there is. I give you the Kayoba Power Series.
.177"cal and single shot only.



No. No it does not come with a bi-pod (or even picatinny rail for that matter). No. It does not come with a 4-16 or 5-25 power scope with rings. No. It does not come with a moderator, in fact the barrel doesn´t even sport a thread to install one.

It comes in a cardboard box that supports the gun within using styrofoam coupled with a small ziplock bag that contains two small o-rings for the pellet probe, and an allen key. In other words not even a bare minimum really.

What it DOES come with tho is a 135£/165$ hang tag. That it DOES come with and TBH i have a REAL hard time getting a grasp on how this piece of kit was produced to be offered at that price point. There HAS to be a catch right?
Cheaper than dirt?
Well. Just about i´d say.

I´ve never really taken an interest in the 177" cal guns. Always thought to myself that what´s the point seeing the caliber and thus the pill weights to be available. Me mainly being into pesting (rats) i still want to be able to dispatch them critters as absolute humanely as possible. At that rate.. "a weak little 177"cal ain´t gonna cut it". Thus the mainstay of my PCP puffs consists of 25cal guns.

Yeah well. Wrong. I was dead wrong even. Certainly my bad.

The Brits have this down as i regard it as they for the most part are limited to their 12fpe permit exempt law. I guess to many that brings that the smaller caliber and lighter weights hands that speeds can be kept up there, for at least reasonable terminal performance on game.
Hm.
Well? What then if you advance this with the insight that.. nevermind the 12fpe, what can the rest of us do? Yeah well, that´s been the rabbit hole i´ve been down the last couple of days.

Thing here is.. at 165 bux is this even a rifle? Not a gimmick or plastic piece of c*ap toy for children?
I can assure you.. it IS a rifle. Hands down. Not only that but a rifle that has come to impress me.



As is, out of the box, these are setup very very limited as far as power. What´s more, i presume for legal reasons, they are clearly marked for 2000psi being maximum fill pressure, which sure doesn´t help in the performance dept.
But.
As things unvailed...BS phrase to keep out of trouble is what them 2000psi is in THIS particular case. It´s that short n simple.

Even as they come out of the box though they´re rather loud to the character why no doubt a moderator is of importance, at least to anyone that wants to keep shooting. On a general whole i´d say "backyard friendly" is exactly that and see NO reason what so ever for PCP puffs being louder than needed.

Right off the bat this there rifle is a contender for for instance the Artemis/Snowpeak PR-900 / Diana Stormrider. Issue with that is.. this piece is more coarse to the build in places while at the same time of better design where it counts and MORE importantly of better materials to the build!
Say wut?

Yes. First thing i did,didn´t even fire a shot, was to rip the piece apart as i wanted to get a grasp on what i was dealing with here and truth be told...
Plastics of any kind are not even on the agenda and what´s more... Mainly machined metal parts, not cast (with exception for the trigger assy housing)
Fit is nothing short of mind blowing. The metal part of it is fit so tight vs the wooden stock you have to FORCE it out of there. What´s more no tool marks, sharp tools has been used during the entire manufacturing.. and i guess we all know what that costs.

Having gone the piece over i quickly put it back together, cocked the hammer to relieve pressure on the poppet on the completely empty tank and.. filled her up.
There´s a Foster fitting up front.. so yeah. 2000psi right. 138 Bar. A Foster fitting even at 165 bux? Yep.

Now.
The tank on this thing, just as on the PR-900 and what not, is out of steel. In contrast though on 2,5mm thickness seamless pressure tubing which coupled with the fact that the valve is on there using three allen screws in shear AT THEIR HEADS and that the other end of the tank hold an adapter out of steel.. using plenty of threads in which in turn the Foster fitting is threaded in place.
2000psi?
Gimme a break already. Spoiler alert here.. i am ALL to aware of the risks involved and ALL to aware that manufacturers recommended pressures should be adhered to in the most anal of fashions one can muster... No argument what so ever.
In THIS particular case though... nah. Just.. no. Them 2000psi is a manner in which to keep power of this thing down. ONLY and PERIOD. I confess to that since the first couple of fills i fill this thing up to 250 bar and it LAUGHS at it.
That being said, it is of course on your own responibility.. I happen to work on metals and am thus fairly clued in on the subject.. hello.
Btw. Tank volume for this one is approx 190cc´s. A rather far cry from the Stormrider 100cc´s..

So. The barrel is on 540mm, which is rather ample for a 177cal gun in my world. Which has also shown to be correct. None the less, even at very mellow power settings the thing barks more than needed for "backyard friendly" why i very soon decided on threading the barrel on the lathe of mine.
Choice this time came to be 1/2"-28UNEF as i had a couple of spare moderators hanging around sporting that thread, for the better. In other words a thread slightly tighter than usually used on PCP´s (1/2"-20 UNF).
One of the moderators being that there "gasoline filter" one you see in the picture. Does a decent enough job of taming the bark i guess but can sure be improved upon, and i will.

So. Barrel threaded, moderator installed. Took a piece of Pic rail off of another gun standing around and bolted a Harris copy bi-pod to it. Then in turn an el-cheapo Nicko Sterling scope on 24 powers..
Filled the tank up as noted and let it rip at 30 meters.

Oh.. let down. What i had was "scatter gun" groups at that distance using 8,4 grain 4,52mm JSB Exacts. Pityful..
However.
From previous experience i know that many mans use some sort of rust preventing oil or crud for the barrels as the guns are shipped at sea.. so off the barrel came to get a good clean.

Some reported that they got groups semi decent at 15 meters.. but that was NOT where i was going. First thing on the agenda was a trip on the lathe to have the crown polished as well as the pellet chamber. Then a REALLY good deep clean of that barrel, this time laughing at the 2000 psi and filling it up to 200 bar...
This being a single shot rifle... Sat down, cocked the thing, loaded her up with one of them JSB pills again aaaaaand....



Right. Nuff said cause see that there is all in all 9 shots fired.
Thus let´s hold right here for a second. Is what i´m saying that with the correct choice of pellets for this god forsaken thing it IS a well working rifle that WILL shoot and shoot rather well at 165 dollars?
Yes.
Yes, that´s what i´m saying.

Does that also mean that this is a well working and completely thought through product at that price?
No.
No it does not. Not by a longshot.



That there abomination.. is by FAR the worst trigger assy i´ve even come to play with. By FAR. It is an "in direct contact single stage setup" and that in the worst kind of ways.
I can not express how bad i think this thing is even on a deeper level. Garbage!



That absolute MASSIVE trigger assy housing then.. contains that. Now.. plz don´t get me wrong... But if effort was put into setting production of this unit up (which is a cost) then WHY not just copycat an existing WELL working balanced unit using a few coil springs instead? By all means, take a look at the trigger assy for the Artemis/Snowpeak M-16 and take it from there!

As is out of the box the trigger is just unusable. Period.
I of course set out to polish all there is as far as contact points and as you can see in the picture there´s all in all three adjustment screws to the thing and TRUST ME when i state i used them adjustments to the absolute brink of reality.
Now the trigger is just BARELY to tolerate, but that´s it. Then.. seeing how this thing has come to play out.. i believe i´m going to adress that more hard core down the line TBH.
Cause see.. the little rifle is worth it. As it turns out.

So. It´ll shoot the 8,4 JSB´s well. What about other sorts of pellets n slugs then? No. Just plain.. nope. Didn´t matter how much i dialed performance either up or down still just plain.. nope.
So i took to "slugging" the barrel to get a feel for what was going on. Judge my surprise when 4,50mm pills didn´t engage the rifling, at ALL. It was like shoving a marble down a piece of gutter approx.
In other words it very soon became evident that the barrels on these measure VERY large, to be noted by that the fun starts at 4,52mm as a bare minimum and then for pellets only.

Hm. So summary thus far is that i believe Kayoba should do another draft on the drawing board as far as the trigger assy and the rifling diameter and twist?
Yes.
It´d basically cost of nothing vs what´s done today, and then thus hand a WAY more usable rifle. But that being said.. it is what it is and i wanted to push forwards right.

177"cal and pests. 8,4´s might do it to some..
A number of years back the semi fabled "Piledriver" boolit was arrived on, in Britain i believe. A sorts of longitudal "banded" slug to work in power limited guns. These come in at a rather, for a 177cal, hefty 21 grains... and now we´re talking as far as i´m concerned! 21 grains, that´s at least usable!
These days tho produced by H&N and what´s more H&N these days also market a 20 grain hollow point slug.
Sure sounds as what we crave right!
A tin of each was ordered. Delivery was a mere few days later and again i set her up to rip.. and this was when i "discovered" that the barrel was simply on the large side. Hits on target to the letter all over the place. If on target at all!

Be adviced though that this isn´t the first time out i´ve had PCP´s running "large" barrel innards. Be that as it may, how do you band-aid that together for something that works regardless?

When i put the thing across the FX brick (the FX radar chrono) it showed me a mere 7,5 Joules approx first time out why i believe the model is intended for sale in Germany really (where the legal limit to be exempt is 7,5J) and that.. yeah well. (N OH do they ever fool around with that.. getting friggin 50cals ok´d at 7,5J shooting rubber balls and what not)

Cause see, here enters a few other "dramas" to be handled. 7,5 Joules and not an adjustment point in sight. Not to fret then cause as stated, this thing is all steel and aluminium..
The end plug for the hammer spring, steel.. so i tossed that on the lathe, drilled and tapped for an M8 bolt. Presto. Adjustable hammer spring. Very very simple mod on this particular beast. Called for to say the least in turn.

However hammer response time was sluggish, let me put it that way, and as i picked the gun apart that hammer truly is of HEFTY proportions!!! Let me tell you!!
For a mere 177cal PCP gun, never got it on a scale in that shape but... i´d say an EASY 100 grams worth. On that note since a few iterations.. it´s now down to 44 grams which is WAY WAY WAY more within bounds. Which in turn has proven itself.

Fact is, this came down to other design criteria as well. The poppet spindle for instance had a protrusion of 8,5mm out of the valve body end. In my book not exactly the smartest of solutions for something to see semi stiff forces and at that rate is unsupported.
What´s more.. just upstream of that valve there´s a hammer stop, again out of steel, that makes sure that what the hammer is able to move is like 4mm worth of poppet.
Mind you.
The poppet of a PCP rarely lifts all that much and within realms 4,5mm is ample and then some. Them unsupported millimeters tho.. not so much why i´ve since basically remodeled the hammer entirely.
Drilled out the hole in the steel hammer stop, shortened the poppet spindle to more sane protrusions (thereby keeping it supported(4,5mm worth)) and simply cutting a sorts of recess the front of the hammer face that runs down into the hole of that hammer stop what´s needed...

Yes. One thing sure lead to another on this one. Net result though was that i now had a much more reasonable shutter time and indeed.. power output was now within realms easily adjustable too.
Win/win if ever.

So all that done, slug time. 20 and 21 grains worth. Aaaaaand back to scattergun again right. No wonder huh?
Yep.
Sure enough, pills way to small in diameter to take to the rifling.. BUT.. this was slugs right and slugs are swaged as they come aaaaand can certainly be swaged an ever so slight amount more/again.



So i turned this little nifty tool to be able to "massage" them slugs to become wider in diameter, and in all honesty..?
The Piledrivers thus far.. not so much. Will need to readress them no doubt.
However.. the 20 grain hollow point H&N´s that measured like 4,51-4,52 out of the tin handed me what could at least be argued to be a group at 30 meters. Like short of two inches worth.
Yep. Down the rabbit hole.. slugs into that tool and a mandrel turned to work with the slugs instead of the Piledrivers.

Bingo.
I came to rest at bumping them to 4,57mm.. and still need to investigate 4,58 as well as 4,60. But already at 4,57 we´re talking less than 1/2" at 30 meters, which will surely ONLY get better with tuning.

So what gives as far as these 20 grain pills then? Well. Do the math, cause if we shove a dedicated for expansion (read - hunting) 177 pill on 20 grains down the bore at inxs of 1050fps and up vs the wall.. we´re talking a whopping approx 70 Joules and see that will be ample and then some for about anything a 177cal could ever be asked to muster.
At least as i regard it.

Sry to say... more to it but out of pictures so i´ll have to continue come tomorrow. For better for worse.

Summary for the day though has to be that this thing really is unreal and has come to impress the living daylights outta me. At 165 USD and a little know-how coupled with a tad of elbow grease.. we´ve got a PCP rifle that´ll accuracy wise be able to hand out dirt naps like it was going out of style to anything within 100 meters when done in essence

Yeah well boys, to be continued...

[BLAHUT]

Nice write up; thank you; I do not have the time - skill - or tools to undertake a project like this.

[dverna]

You do amazing work and I really enjoy your projects.

1/2" groups at 30 meters is very good for a sub $200 air gun...If a "normal Joe" can get that accuracy. By that, I mean doing simple modifications. Most people are not going to be able to do machining.

I may be less talented than most so bear with me. I have a DAR that needs some trigger work. I have read it is "easy to do", but I am not confident about tearing into it. I end up shooting a Daystate because it works out of the box. Yes, the Daystate is 3-4 times more expensive, but I am willing to make the investment to get a gun that is a joy to shoot.

This gun you are working on has a fatal flaw. Barrel diameter. There are folks that can live with a poor trigger on a "cheap" gun (as I do with the DAR) but if the gun will not shoot commercial pellets accurately, it will fail.

[Racing]

In all fairness it WILL shoot with off the shelf pellets IF JSB Exacts on 4,52mm is used.
That´s the caveat in all of this me thinks.

But yeah. I´m with you.

Then. Agreed on machining, all good. Saying that tho i believe we should distinct between machining and DIY mods.
Drilling and tapping for an M8 bolt on the vise in the garage.. sure.
Machining a hammer? Not so much.
Handing the barrel a polished crown and pellet chamber using a regular drill motor? Sure.
Maching the valve exhaust and receiver for a more normal transfer port setup, again not so much.

... and that list goes on.

So.
Can this rifle be had to shoot with a minimum of effort by the DIY´er?
Yes. Yes it can, but at that rate the DIY´er NEEDS to know what needs to be done. Which often times isn´t completely self evident. Hence this, what will be, rather long post.

None the less a fact stands and that is that this rifle will hand true PCP rifle performance at coffee and change. That´s kind of not debatable.

To morons like me and the likes in turn, this is a platform to work from that´s about unrivaled if you ask me. If not in the loop i´ve done my fair share of budget and midrange hang tag PCP´s by now and this is by far the cheapest of them all.
Thus i find it... shall we call it pleasing (?) that a PCP rifle can be had at that price point that´s a real rifle, at ALL. For the more in depth and advanced DIY this piece is an absolute gem.
That simple.

[Racing]

As promised then.
Again spoiler alert cause this got silly. Just plain silly.

Again, sry for the delay due Pixlr and the pictures. Brings that it won´t all be chronological but.. we´ll have to cope anyways.

Yeah!
Topic at hand!



Like i wrote above, might be a tad coarse to the build in places but on the other hand stuff like the valve, the fill port and end cap.. as you can see for yourself these parts are machined aluminium n steel - and rather neatly done at that.
Note the rather long spindle on the poppet, then bare in mind that it´s been shortened!

But of course some of the ports have been opened up. Mainly as i believe in that to control a PCP we should focus that in ONE point/place. Thus various openings have been reset to become more on par - for lack of better description.



Uhu. The piece lacks a traditional transfer port on a whole. Kayoba obviously arrived on that the seal between the tube and the receiver.. well it´s just a piece of turned hard plastic. Presume POM, and of course that won´t seal shut as we´d expect why i took an 8mm end mill and shoved that down the opening on the tube into the exhaust port of the valve.
Then did the same for the entry on the receiver, in the end making sure both ends of the transfer port kept o-rings on 8mm diameter to make for a MUCH more positive seal. As it turns out... yeah.
Cause even noise level went down massive.. hidden leaks anyone?

I put the thing back together, took my time doing so. Yes, there´s pics of the hammer i write about per above but.. Pixlr... Them coming up tho.
One thing i´m going to try is to recut the hammer face even deeper for added ability to go deep on the poppet. As is i have no idea where it ends up at the moment and plan to install an o-ring on the poppet spindle to "see" where it comes to a rest and thus get an idea of poppet stroke.

So yeah. The thing went back together and that done i took to making a fresh mandrel/plunch to reshape the H&N hollow point slugs. Turns out.. i must have gotten that right.
Did the same for the Piledrivers BUT.. after today, having been able to go about this in an orderly fashion, it turns out the Piledrivers are simply to deep for the chamber of this Kayoba.
In short 21 grain Piledrivers bottoms out vs the lead in it isn´t even funny and you end up closing the bolt using brute force. So no wonder them pills won´t group on target.
However.
The H&N hollow point 20 grainers will and let me tell ya...

It got silly.



Cause that there is the payload, seven shots in all, out of a 165$ gun using 20 grain slugs on target. Really? I mean, really? HELLO!
To state i´m happy with the performance out of this thing is being very diplomatic about it. Never had i assumed in my wildest thoughts..
165 bux, a bit of know-how and some elbow grease. In essence.
So yeah. Silly.

This promptly brings that i can state with confidence that a worked over Kayoba PS in 177"cal can hand out dirt naps like no tomorrow on anything pest within 100 meters. No doubt in my mind.
What´s more that there target isn´t me "going full retard" as far as the shooting end of it. More like, bring the gun up take aim and fire.
Granted, i DID spend more time on the trigger. Even taking a look at replacing the entire trigger group but.. looks like a tad of work to make that happen and as such.. not the first priority on the agenda.

Nah. First up i´m going to make it even more silent in operation. A different moderator, one of my own designs, is to be introduced to the muzzle there... Second up i´m going to look into making that Artemis mag fit.
Yes.
It´ll entail cutting into the receiver on the mill of mine but.. it is what it is right. What´s more i truly think the gun would benefit from a sidelever setup, i really do as i´m NO fan of bolt actions when it comes to PCP´s what so ever.

The real win of the day tho?
Guys. Just look at the target up there.
Nuff said.

[Racing]

Yeah.
So for part three of this saga then.



As told earlier the hammer has been severly modified. Even more so since yesterday, and is now closing up on 40 grams flat. But from the picture alone.. you get an idea.
Note that front "knob" that i turned on the lathe. Uhu.. today 1mm deeper even and that coupled with playing around with hammer springs and hammer spring settings..

Ok? Where we at?
In short it is now capable of shoving 20 grain pills out the muzzle at 1065+fps at will. NOT where i´ve had it come to rest but the CAPACITY is sure there. As many of you are aware slugs are after all slugs and often enjoy being sent downrange at higher speeds than pellets.
As such, where´s the limit?
Where does this thing stonewall? Welp, i for one see no reason what so ever making PCP´s go supersonic. At that rate, in my opinion, you´ve come to misunderstand the design goal.
Thus 1065+ really is on the verge as far as i´m concerned, and this done on a bit "varying" diameter transfers but.. smallest is 4mm that said. The beauty here being the span of the piece cause it´s just as happy at 400fps throwing them slugs.
That´s quite a span and indeed it of course thrives at certain speeds more than other. They´re all like that right.

¨

Yes. It actually sports a de-pinger too. Nothing all that fancy to write home about, but.. the through hole of course got enlarged not to become a flow hinderance upstreams of the actual valve. Any and all pressure drop at this point spells death to repeatability so..
Be adviced though, as this IS a contender for the Stormrider in my book, that the pressure tank is a tad larger than on the Stormrider. None the less, making power sure gulps air..
..and per usual that de-pinger doubles as a mounting outlet for the pressure gauge.

On that note.. the pressure gauges we see on PCP´s, NEVER take what they say for gospel without having them calibrated. I don´t CARE how expensive your gun happened to be.
I´ve seen them off by an EASY 60 bar.. and in this case the gauge gave up on life completely... as i fill the thing to 250bar. Ergo that gauge needs replacing..



Although today has been about trying different hammer spring combinations out i also got around to revamping an old moderator of mine that i made a while back. Difference in sound level is.. eye opening to say the least. Yes. When done to WORK instead of just look impressive.. this thing turned real silent in operation. Real happy about that.
As you can see.. the scope n rings got replaced. I really can´t wait to take this thing ratting but.. it will be with an old Yukon ontop and that brings i need to pick a pair of 30mm rings for dovetail (11mm) up as i lack that.

To be honest.. i think i´m going to run the thing at a number of speeds using them H&N 20 grain slugs upcoming, to settle where the gun feels in harmony. At 1065 it´s like getting on a race horse approx and.. albeit fun for a while i sincerly doubt that that is where the thing will "lean back" and feel at home.

Knowing all to well what slugs crave to work as intended.. Still going to be very very interesting to see how this piece will make them 20 grain H&N´s work on target.

Already where we´re at we KNOW that this thing is accurate it´s silly, being what it is after all.

Upcoming then?
Yeah well, what i also did was first up again check what it´ll take to make that Artemis/Snowpeak mag fit. Is it really needed? Nah, not really but.. convenient - for lack of better words. Believe that mag to hold 9 pills, and it´ll take the 20 grainers with ease.
Second up, scavenged an old Hatsan AT-44 receiver to just look into what it´d take to convert this thing to sidelever.
As is it´s starting to get up there as far as force needed to recock the thing, and that sure wasn´t the idea. Fact is, since a while back i just fail to see the reason for "bolt action" PCP´s. Them being linear, for lack of better wording, is just plain waste in my book when a sidelever system will add a gearing more or less as we see fitz..
Such a case scenario tho that will be from scratch.

So..
To be continued.

[BLAHUT]

Again a nice write up... I am wondering? how much time and $$$ you are spending on remaking, redesigning this $165.00 air gun ??
Guess I will just stick with my cheap 753 - 853 daisy match guns and just shoot....I have better match guns; but these are the cheap ones and shoot...

[Racing]

Money, as in cash layout for parts? About nil.
Don´t get me wrong cause a scope, rings, a bi-pod of course costs money. The externals. They always do so nothing specific for this, or any other, rifle really. As for the stuff that´s gone on this gun, all of it picked up used apart from the rings (that are cheaper than dirt new from the same place i got the gun) or handed to me for free (scope for instance).

But on actual, especially internal, modifications to enhance performance?
About nil. Yeah well, maybe a few bux on o-rings where needed now n then?

Actually, ditto for the moderator. Just some spare steel i had laying around, so cash layout about nil. Uses standard freeze plugs and the Mrs Wettex rags within (yes, freeze plugs for a car engine, and no she still hasn´t noticed! ).

One of the percs of owning a lathe, a mill and a decent TIG welder and what not i guess. Left overs from my racing days.
Costs as in running the lathe or whatever? Lighting. Running water, heat and toilet paper at the shop.. Sure. (I design and build tube amps remember.. )

My time tho, different matter.
Point here, it´s my hobby. What i do for a living is tube amplifiers why guns (in general) are a very welcome "in total contrast" sorts of spare time.
Know how? Sure, i guess. There´s of course been a learning curve to it. No argument on that one. Some of it in turn, like bumping up diameters for a given pill as in this case, just plain common sense and a bit of materials to me.

As i regard it that´s one of the beaut´s of PCP´s. It´s WAY WAY WAY more about knowing how to than expensive hotrod parts. Again don´t get me wrong as i think we should compare apples to apples here. A Leishy, a Daystate, an FX.. different ballgame and a way different check book too.

For the more "common man" guns though, yes. Most certainly so that it to a very large extent is about knowing how n why and i´m by FAR any expert on the matter! I make these posts as i´m absolutely positive there´s others out there that can benefit from them.
So.?
More along the lines of the advanced home tinkerer maybe?

For instance.
If you look that post on my Kral Puncher Breaker up.. in there´s the story on how i was adviced to move to a 2mm dia poppet spindle, and what it´d bring. Adviced by those more in the know than me. I just did what i was told, but the point here is that there´s rather few that does for some reason.?
So. I did, and got to tell about the outcome. Learning as i went.

Herein lies the beauty of this, as i see it.
That we CAN pick a super low budget PCP up and make it haul IF we´re just aware/told how to. Some of them cater better to this than others. The mentioned Stormrider/PR-900 as well as CR-600 and in turn the CP-2...not the best material of choice for the valve housing for instance.
Of course i can´t speak for all but I sure got fed up with the material the valve is made of and due that made my own valves out of way higher quality material.
Of course..
Would i have had to pay someone to do that job the entire project would have been out of bounds. Completely and entirely. So yeah. For the more or less advanced DIY folk.

That being said.. again from my racing days. The DIY crowd is often better at what they do than they get credit for in my experience. To the point where they´ll even craft ways to for instance "mill" something on their die hard bench drill press or whatever along those lines.
Pro looking results? Maybe not, but many a time a working part in hand all said - which in my book is the imperative here.

So.
All said and done this is a hobby. Yes i do take on jobs for ppl that ask me to, while making very clear that it´s still a hobby. Brings that i don´t say yes to all that walks in the door, nor will i ever.

Match guns in turn, sure.



Do them too, several actually. Here the Sauer STR with Spuhr mounts and what not.. Powder burners mainly PRS and ELR.

[Racing]

Said n done.
Really starting to look like an elaborate piece of kit, and to a degree i guess it is. Took the thing ratting, which paid off so now i´m that much wiser as far as using 177cal HP on rodents.

Set it up rather hot as i made the scope hit to POA and at that rate.. suuuper accurate.
In a word them small pills on rats, devastating. It´s that simple. Even in 177cal headshots using hollows = decaptiation. In short as humane a dispatch one could ever ask.

Scope ontop is an old Yukon that´s seen use on several PCP´s over the years. Not exactly the last iteration IR anymore, but it still works at least and the rats sure won´t notice vs the Pards, Accurfires and what not.

And again.
Can on there is one of my own. I can not emphasize the importance of having a can dialed in enough via the use of a dial indicator. In my case on a lathe. The less the runout the smaller the through holes can be kept and the more efficient the moderator.
It is that simple and indeed that home brew can there makes this piece about dead silent. All to aware that moderator threads more often than not is 1/2"-20 UNF .. kind of a pity as 1/2"-28UNEF sure helps making things end up in the same place time and again as you take the thing off n put it back on.

[dverna]

Great job and write up!!

[Racing]

Hey thanx!


Yeah ok, so for sorts of an update then.

Have used this thing on the rats and mice tonight again. Beforehand i of course made sure it prints as intended, and the mere fact of it is that the thing IS laser accurate using the 20 grain H&N´s.
Due that the two rats of tonight never stood a chance. That simple.

So that being said, will a mere 177cal be enough to hand a humane dispatch of rodents? No matter the size?
Well.
It being as accurate as it after all is that brings that i take head shots and that of course straighten out any and all question marks.
The coward way out?
Regard it as you wish, fact still stands. It´s accurate enough to pull that off within say 40 meters (Just short of 44yds?). Would i trust the thing out to 100?
Well.
That remains to be seen, but truth be told i kind of fail to see the reason. Point in case being that i´ve got a downright plethora of 25´s that´ll handle that, and then some, with ease... why i don´t really see the point in stretching it for the 177cal.
Within them 40 meters tho.. short notice of the vermin. No two ways about that and i´ll refrain from posting pics of them to keep the site family friendly.

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Need options? For close to that price, you can also get a Beeman Chief for under $200 on a proper deal. Here it is on Amazon, if you live in a free area where they will ship one...
https://www.amazon.com/Beeman-Chief-...LH8?th=1&psc=1

Near to this are the Benjamin Maximus/Discovery (I think the Discovery is out of production), and the Diana Stormrider, which is a rebranded SPA rifle.

These guns won't impress any gun snobs, but they are minute-of-squirrel accurate and you can fill them with a hand pump that looks like a bicycle pump. They are also lighter than most PCPs for field carry, more like carrying a 10/22.

[Racing]

Need options? For close to that price, you can also get a Beeman Chief for under $200 on a proper deal. Here it is on Amazon, if you live in a free area where they will ship one...
https://www.amazon.com/Beeman-Chief-...LH8?th=1&psc=1

Near to this are the Benjamin Maximus/Discovery (I think the Discovery is out of production), and the Diana Stormrider, which is a rebranded SPA rifle.

These guns won't impress any gun snobs, but they are minute-of-squirrel accurate and you can fill them with a hand pump that looks like a bicycle pump. They are also lighter than most PCPs for field carry, more like carrying a 10/22.

Yeah. For all intent and purposes the Kayoba power series PCP rifle IS a Beeman Chief, of the first model.
AFAIK, to be said.

The Diana Stormrider/Artemis PR-900 and so forth (exact same guns just different brand names) i guess compete in the same bracket but if the Beeman Chiefs are anything CLOSE to what this Kayoba turned out to be within... sry but then these Chief guns win out big time in my book.
Reason is simple.
These are made to be picked apart and serviced more than once, which the Stormriders are not. Valve and what have you are of way lesser quality on the Stormrider group of rifles.

To many, i guess, it comes down to that the Chief lacks a mag. Single shot only.
I can appreciate that but put in context a PCP rarely needs to be "fast fire" in my book. For pests they´re certainly accurate enough for "one shot, one kill" no doubt why follow up.. i at least have yet to experience the need when on pests.

That being said i actually keep a semi too, a Kral Puncher semi, and albeit a "nice to have" feature i guess i have yet to prove a need for it.

Nah.
Purpose of this post, to large extent at least, is to show that there´s REAL cheap PCP´s out there to be had that honestly does work as intended. True.. this particular one in need of some rather "special" solutions to become all it can be, but to a degree besides the point as it´ll shoot well enough and then some using factory JSB diabolos on 8,4 grains - if you´re content doing so.

So yeah. Reply to the question not asked owning a PR-900 and a CP-2 converted by me from Co2 to PCP.. where it me in the market for my first PCP i honestly would consider the Beeman Chief over the Stormrider.
Again.. this is NOT me coming down on the Stormrider as to most.. they don´t pick their PCP apart first thing like me, as the idiot i am
I´m just stating that those of us that tend to DO.. the Beeman comes out ontop as being the WAY more serviceable rifle. At least in my opinion.

Then again.. for a few bux more we´re into for instance Artemis/SMK P-15 territory if you pick it up used. Then sporting a regulator and what not, and although an old design by now.. that P-15 or P-35 is still a very viable option to most i´d say, n yes.. i own a P15 too.
EXTREMELY light little bullpup rifle, accurate beyond what most could ask and can be picked up at reasonable rates these days used.

But.
That´s for another post tho.

[Racing]

Yeah ok. So for the dual hammer spring setup i run, enough of the stock bolt handle made to fit a 5yr old.



Then for something that ATM at least´s got me a tad puzzled. This is a mere 177cal piece right and the actual probe PIN that serves the pill for the barrel is stock on a 2,6mm diameter.
So.. thought to myself that sure ain´t what the Dr ordered so out the probe came and i thinned that thing to 1,6mm diameter. Nope. That sure wasn´t the flow hinderance.
Where i´m at i´m seeing like 1070fps max and that´s it. Need to figure out where the issue is at cause in my book this thing should be doing super sonic speeds no issue what so ever..
Not that i strive for that, i just want to understand where the bottle neck is at.

[Racing]

Might be i found out what kept performance to them 1070fps...
Just a brainfart on my behalf in such a case cause i sure upped the "under the seat" diameter, upped the through diameter on the de-pinger yadda yadda..
But then there´s sorts of a threaded "lid" on the valve to keep the poppet return spring in place and guess what.. Yeah. Upstream of the valve i had a mere 4,5mm through..
So.. bad on my behalf and rectified to a more sound 7,5mm.

Then.
I guess an el-cheapo project like this could be run up the proverbial wall and i guess that sooner or later we´re getting into pure folly really. So yeah, as sorts of a degree of self critisism.. guilty.

Being that as it may it still IS such that this Beeman Chief rip off ain´t all that much better than the Stormrider as far as tank capacity and as power goes up.. it really becomes more and more of an issue after a certain point.

Now. Just like on my Stormrider i find that going berzerk as far as this, installing adapters for buddy bottles and what not, is outside the scope of this sorts of gun.
I for one find the lines of both this Chief and the Stormrider.. if not lovely at least "rifle looking" and would much prefer to stay that way. So yeah, i do own a lathe, a bridgeport and a decent TIG welder coupled with the know how to swing them so..



If my math is on the money, and it sure is, this there tube will increase capacity to the north side of 300cc´s while still staying within the realms of what the stock hands.
So.. win/win. While at it i´ll get to reposition the Foster fitting where i can fill up to hearts desire without interfering with other parts, like the moderator of mine with the Foster at the end of the actual tank.

[Racing]

That sure escalated quickly. No harm no foul though. I presume you guys get an idea where this is headed..
Overkill anyone? Anyone?



Yeah. Inletting to be done. But again, it hands the concept idea me thinks already as is. Foster will be up front again, tank this time both fatter and in turn those few millimeters shorter rendering it´ll be 100% accessible from now on out.
Pressure gauge, yes a fresh one is needed as the stocker is about as shot (duh!) they become. Will use the OEM cutout on the stock for that.
Be adviced as far as the proximity between the tank and the barrel. Not all that much to play with and indeed i both threaded and used a jig before hitting the thing with the TIG welder.

[Racing]

Inletting.. indeed. Apart from it now being on a tad more than 300cc´s as you can see it also provides ample clearance vs the moderator as far as the Foster fitting.
Actual Foster in itself is not the stock piece but a self contained unit. Way small proportions.

Pressure gauge, i turned me a weld bung that i set onto the main tank and the actual pressure gauge is somewhat larger in diameter so.. again inletting.
That being said..



With any luck, if it all pans out, i´ll be giving this a first whirl come tomorrow. All the "little pieces", that i know of, have been ironed out.
Will report back.

[Racing]

In all honesty this has grown into anything BUT ultra budget. Pushing the envelope though i have to go on record and say i´m very very pleased. Yes. It hands power being a 177cal it´s insane.. but that´s not the point of this build.
What is is the span that came out of it.



Uhu. Pushing through "the barrier" was done in a heartbeat using the 20 grain H&N slugs now. A heavy supersonic *boom" was the reward and altho i haven´t checked it vs the LabRadar (the FX brick comes to a dead halt at around 1100fps) i bet that as it pushed through it´ll go quite a bit faster seeing the lower resistance the other side of "the wall".
I came to turn the hammer spring adjuster out so it came to settle around the 1030-1040 mark and at that rate i get an easy 30-35 good shots out of it before i see changes in print. Ie; how it prints on target at 30 meters.

Is this for everyone? Far from it as it takes both knowledge of materials as tools and in turn knowledge of how to and so on.. and let it be known that making your own high pressure cylinders is NOT for the faint of heart. You HAVE to know what you´re doing, otherwise this can turn lethal in a heartbeat - and noone wins.

That being said what´s been done here is turn the cheapest of the cheap into something anything but all said and done.

Happy?
For the time being, yes. In fact it all DID pan out and sighting the thing in became childs play. It shoots very very well and at that rate i believe we to be fair need to keep in mind that the barrel on there is the stock unit for a 135£/165$ PCP gun.

Now i need to come to terms with the piece. Get to know it, kind of all over. For the better though cause what i´ve experienced so far has been something new to me.
What i´m getting at is of course the 177 caliber, where this unit is a first to me. No matter how we regard it though pushing them 20 grains H&N slugs supersonic most LIKELY means this thing is pushing 80 Joules when let free to run b*lls to the wall.
Seeing the minescule caliber and thus pill weights.. that´s a fresh one to me. Actually was gifted a tin of H&N "Rabbit Magnums" @ 16 grains and that was just.. a laughing matter. Super sonic in a heartbeat..

Learning curve i guess.

Anyways. Now to get to terms with it in its new guise. What i´ve experienced thus far has all been one massive positive to be honest. Let´s see what i think in a couple of weeks..

[Racing]

As i was up for using this thing on the rats tonight i took a seat to sight it in more seriously. This.. is impressive, that there is 9 shots taken at 30 meters at dusk.
This is the performance this unit´ll hand you given a tad of TLC, and we´re talking a 135£/165$ gun here.
In my book that´s nothing short of insane, cause handing that performance means that it runs with guns 5-10 times as expensive, which is saying something me thinks.



Sure. Granted. Seeing the work invested here it really isn´t an ultra budget PCP anymore but none the less. Still the stock barrel and still the modified original valve n poppet.
Thing slings 20 grain slugs through the sound barrier like it was nothing at will. Settling for 1060fps approx renders that there. *shakes head*
Well lads.
Consider me impressed.