BSA R-10, now what?

[Racing]

The mesh i believe is common speaker grille.
Nothing fancy what so ever.

Came to dig into the setup with the banjo and so forth a little deeper.
Cut the window for added throw on the receiver. Flattened the banjo, and will rework that even further. Played around with the fit between the steel nose piece and the plastic sleeve.. i dunno. I really do not, but will give that sleeve one more try.
The probe in turn, i believe iīll just make a fresh nose for it, then out of higher grade steel. The threads on that thing are worn, albeit the piece is new, and i feel the material used is just plain cheap. Thus a fresh nose out of higher grade steel iīd say is on the agenda.
The cutout on the probe for the ball bearing, might be splitting hairs but truth be told.. either that cutout needs to be moved a bit OR the new nose piece set at a different angle and as the nose piece will be anyways.. you get the idea.



On the barrel in turn. I believe itīs speced as on 1:18 and sans a choke. Have pushed a few pills through it and it does measure on the money at least. The drawback here is that it will turn an already rather long rifle even longer, by just shy of 20cm.
But. Iīll give it a go. 1:18 should support all the slug use iīll ever throw at it at least, being very well aware that thereīs those that feel 1:16 or even lower would be the ticket.
But again.
This is a pesting tool. Not a long range pcp bench piece.
As for that breech piece.. undecided on material yet. But.. brass? I guess?

[Racing]

Yeah. So enough of this bolt flip issue already. Opted to cut the probe at the joint where it changes dia, and took it from there. New nose out of SIS-2241 stainless, a "slight" difference vs the stock papier mache stuff. D*mn that stuff takes a bit to cut into.. That M3 hole for the banjo bolt..yeah. That banjo is on there now as were it welded in there.
In turn, yes. As you can see a slug pin. It works on the R-10 as long as kept short, and good for us it really doesnīt need all that much in that dept all said in the first place. So all good.

Spent the time needed to ensure 100% lockup as the banjo is pushed rearwards by firing pressure. As you can also see the banjo in case has had TWO of its "sides" made 90deg to each other and yes.. it works. Rather well at that. Thereīs a slight axial movement on the probe, and i have to shove it inwards to "unlock" the piece now. Not by much, but enough to ensure that as the probe is pushed rearwards upon firing itīs going nowhere.

Then @ RKR.
I took to really compare the two barrels today. The stocker is on 470mm as it turns out. In other words 18,5 inches. The Evanix barrel on 650mm, or 25,6 inches if you wish.
That the latter will hand increased exit speeds i guess is clear to all, but shoving pills through both of them the BSA barrel is no doubt more loose vs the Evanix one but..
Any appreciable choke on the BSA piece, no not really. WTeff?
What iīm saying is that it seems theyīre both on 1:18 twist (sure looks very similar too as you look down both of them vs a light source) and where the Evanix barrel sure doesnīt sport any choke what so ever the one on the BSA barrel is very slight.

Could this be the reason iīve seen so differing results using slugs vs what you have? If so, why did this barrel leave BSA like this in the first place? Seems a bit.. "not in total control of QC" sorts of? Or?

Anyways.
I donīt mind making one off parts one yota, not at all, but there sure DOES need to be a purpose for them... and iīm starting to think that the goals iīve got in this case... an about 50cm barrel will work just as well as a 65cm one? End idea is to, no matter pill weight, keep beneath 1000fps. See no reason to push that what so ever.
Sure. Theyīll of course behave slightly different, no argument on that one, but that being said..? I sincerly DO find this a bit peculiar, i have to say (that there with the BSA barrel).

I guess what iīm saying is that iīll take to fabricating that breech piece to make the Evanix barrel fit the BSA... but REAL unsure as to if thatīs the route to take all said.
As stated, i had decent groupings using the BSA offering shooting slugs of various weights as well as heavier pellets.

[Racing]

Unit is back up and running.
In essence at the same power level as previous, throwing 25,4īs @ 960.
Thing here is... i want to really take a sit and evaluate what itīll thrive on. Cause as a pesting tool iīd say weīre there.
Even managed to repair the busted mag to at least usable status, for now until replacements arrive.

Nah. On a whole iīd say weīre back on track. Unitīs doing what it should without any particular fuzz, and the mods pulled as far as bolt flip =100%.
Bolt doesnīt move at all upon firing.

Giving thought how to handle that there with the regulator in turn. For now it at least seems the thing does what it does fairly consistent.

If it happens that the thing shoots better using heavier pills i guess iīll have to reevaluate and take it from there. Actually had it setup to handle the scaly tails for tonight, but as we just got a cold streak.. not even the slightest sign of life through the thermal.
Itīs no doubt ready for action though.

[Racing]

"King of the late brakers (at the race track)"
Kind of like.. all excuses as far as target work as well right 

Nah. Measured distance, just outside the shop, taken with an LRF is 43 meters (47 yards). Got like 80+ to play with (closing up on 100 if i stretch it actually) but not so during business hours, for obvious reasons i guess. So.. 43īll have to do. At least for this session.

This was far from prime shooting on my behalf. Can do way better than whatīs in the pictures but.. it is what it is seeing the cirumstances and that bench rest wasnīt really on the agenda. More so just practical results from putting the gun up n fire away, as you do when hunting.

Setup is "mellow". Ie; a mere approx 130 bar, hammer spring for an Impact wound in a fair bit, ports on 5.5mm (22cal) and in turn a poppet on a 2mm shank. Barrel the stock BSA offering that came on the gun, measuring 470mm (18,5").
My shooting today was so-so at best as we just got freezing temps and at work.. iīm not really dressed to handle that. So it got cold REAL fast, let me tell you. Way to cold to be precise dressed the way i was.
Anyways.
These were all 5 shot groups.



This 216" diameter Knockout slugs. Nothing all that much to debate really. At this point sending them around 960fps but that being said tuning, as we know it, none what so ever. This goes for all pills/targets. Tuning, simply havenīt had the time to yet so pills were sent as the pew stood and done deal.



Ditto slugs just the 218" dia flavor. Flyer is no doubt me (cold was getting to me already..)



Then the cold really got the better of me. This done using JSB 25,39 pellets. Gun has shot these way tighter earlier so that there sloppy result is just plain me. Cold enough for no retake.



This tho is where it gets interesting. This the result by H&Ns 40 grain pills. To be noticed here is that this is single loading, no way these will fit the stock mag.
I find this interesting cause without actually measuring exit speed here iīd wager that weīre MAYBE talking low 800īs here at best - if even that.
The rest ontop sailed at approx the same speed seeing they weigh approx the same (25,4 grains).
Why worth of notice? Well. The barrel is on 1:18 right (which i can attest to after looking down two barrels at the same time where i KNOW the twist on the other one to be 1:18) and as such not exactly optimum sending them there torpedos at 810 or 820fps (as an educated guess (see above)).
I absolutely bet them 40īs would shoot on par with the Knockouts handed the speeds they crave n need. I would really like to see them sail along the north side of 1000fps to be honest, know them to perform well at that rate  (read - more accurate)

What that sums up to, at least in my book, is that this thing can be had to handle about any pill out there "fair" at least. As much as i appreciate that groups will open up with distance itīs always nice to have options. For really windy conditions for instance, them 40īs are bound to buck that way better than any Knockouts ever will.
OTOH Knockouts for more sane conditions will hand speed real fast, which equals massive expansion on target. Ie; a humane a dispatch as we could ever ask for.

Issue, as i see it, is air consumption. Where weīre at itīs anything but efficient (i took approx 14-15 shots per fill), this much is real clear. Seeing that i guess a SSG and a Blast tamer is the next natural steps IF the latter can be applied.
Point being that i guess the two next steps to be of notice (or three really) is a larger bottle... followed by a different regulator... and then a SSG.

Know that weīve been ontopic fabbing a collapsable such, thought iīd look into that.

[rkr]

Looks like you are doing well with those JSB slugs, 40 grainers spread out a bit but higher speed would probably help and that's still in good .22lr territory. I'd stick with those JSBs, those are fair groups and will save you air + get flatter trajectory. Unless you plan on shooting past 50M you gain little with heavier slugs, of course if you do plan on shooting 100M then 40 grainers at 1000+ fps should be your goal.

In my tests Blast tamer didn't work with 2mm valve stem, too slow valve closing so it banged on hammer latch pin while valve was still open causing extended opening. I'd suggest working with SSG to save air.

[Racing]

Reference points.
I hear ya.
However, i compete at both PRS and ELR as well as PRS-22. Yep, powder burners the entire way no doubt. Got this Anschütz hardware I stuck down a KRG stock for a Ruger 10/22 (that didnīt fit worth a s*it let me tell ya) why iīd say 22lr territory.. it depends.
That Anschütz will hand me 5 shot groups the size of a small literal thumb nail at 100 meters using SK Long range..

Anyways.
Yeah. Plz keep in mind that this unit truly is a work in progress. My point is/was that the stock BSA barrel will handle slugs just fine, and to top that off in contrast to many other pcpīs iīve tried it seems it couldnīt care less what size Knockouts i feed the thing. It just shoots it all well.
Thatīs kind of impressive to me.

Iīm 100% positive this can be improved upon in turn. Down to setting the trigger to work decent cause as is.. itīs a good ways bit off in that dept yet. Fact is, from an ergonomic standpoint the entire thing needs to be setup, to ME.
All in due time though.
The thing is stacking scalps already, two last night and one tonight.

Which raises a Q to be answered really cause.. pest control alright, question is to what level?
As i get them relatively cheap Knockouts to zip the way they do iīm thinking theyīll behave no different, better if anything such a case, driven a wee bit more stiff.
Say 1050.

Thatīd equate to 85J/63fpe which as far as iīm concerned is all needed and then some even for longer shots on the scalies (easily 80 meters).
From a practical point of view iīd say 40īs are out.
Sure. The receiver could be reworked and a different mag made to fit i bet, but to what avail? So.. no.
That leaves us with 34īs at the most and shoving them down the tube doing 1050 would render 102/75. The thing here though is that whatīs important is the breakup on impact. Or more so expansion, and i bet the difference on target using the Knockouts vs any generic 34 grain hollow... not much of a difference. 1050 is 1050 no matter how you regard it (read - pill weight)

Iīve been after them s*umbags for a while and hereīs the bottom line.
As pcpīs can be had to be as accurate as they can headshots is the norm. Doing so using ANY modern hollow point will in practice bring what could best be described as decapitation.
You to the letter blow their heads off.
Fact is, tonights scalp.. exactly that. What iīm saying is that from a practical standpoint the actual result on target will amount to about the same thing using 25,4īs vs 34īs. Yes, a marked difference in power, agreed. Thing is.. got no need for it. Rats are rather "soft" targets.
(Btw, the last one last night was a severe fatty. About 1kg worth)

Seeing this i think the "new" plan/goal will be to see how Knockouts behave in an export model R-10 exiting around the 1050 mark. Ditto, believe iīm going to check how well that probe mounted seal is really doing.
When cutting the groove i basically just went off what BSA had done, but it has dawned on me that BSA most likely never ran these units at the speeds n powerlevels i am (or RKR for that matter).
What am i getting at?

Well. As youīre aware i do make my own moderators...and @ RKR, weīve been over this.. how an increase in shroud diameter from the stock 25 to 28mm actually DOES affect note and attitude of noise suppression. Be that as it may the can up front in turn is real effective at what it does so.. where weīre at weīre good.
Raising that ca 100fps though, another matter - which i know from experience.
One of the main culprits being that as you get the entire setup down as far as diffusor and moderator being really linear vs the barrel and in turn the setup is sealed off as intended.. we start getting into the little things.

Donīt get me wrong! Where weīre at this unit is no doubt very silent in operation, thatīs NOT an issue. What i foresee though MIGHT become an issue is that as amount of gas n pressure go up the actual o-rings might start to dance around to hearts content.
Experienced this times enough as is, and have learned a trick or two down that road no doubt. Near future will tell i guess.

Feel the exhaust note is a tad "snappy", which i absolutely bet is from the minor diameter shroud, coupled with that the barrel is on a full rather "fatso" 15,5mm diameter. Ie; not all that much volume left all said.
No matter.
As described above i just installed a diffusor as is sans any sealing what so ever AND in turn on a rather large through hole so i guess what iīll do here shortly is set that diffusor more proper as far as dimensions and in turn seal it off with an o-ring within vs the actual tube.
Thereby creating two separate entities from the one tube really. In turn as the shroud part of it carries filler now i believe iīll drill a few pressure relief holes out rear. Wonīt really amount to anything sound wise escaping but will no doubt cut down on that "snappiness" there current.

1050.
Got a 22cal Reximex Daystar sporting a Huma running at approx 170bar spitting Knockouts doing that (on a smaller plenum than this R-10 though). That is a wonderful accurate piece of kit hands down. No shroud, just the moderator, but still rather silent in operation. WAY WAY WAY more so than anything store bought.
What iīm saying by that is that this no doubt can be pulled off, and i like my puffs SILENT. As in "Hollywood silent". Donīt wanna bother ANYONE when out doing what i do. Well, besides the rats that is of course.

Still got a few trix to pull as far as this R-10 and performance. When i go SSG in turn i will replace the Impact spring entirely and run a dual setup. Mainly as this hands smoother "progression" in my book cocking the piece.

One thing i did today on that note was bring out a larger buddy bottle, mainly just to compare really. One of the generic aluminium 250bar jobbies, when it struck me.. i can make this happen real fast. 
All i need to do is turn an adapter from the BSA style thread to M18 generic standard and done deal. Then just reuse the entire BSA valve and so forth as is.
So..yeah. Thatīd double the capacity of this unit in one blow and if iīm to hop it up even more to make them 1050.. it is needed.

Hm.
Iīll keep you guys posted, you can take that to the bank.

[Racing]

Aimed at RKR really but feel free to chime in whoever...

This whole SSG thing. Got me thinking.

The idea is to have the hammer free float amount X before hitting the end of the poppet shank right.

Then.. hammer weight is of course of importance, which is the hammer and any parts thereof coupled with half the spring used.
Right.

Now. What is it that says that the SSG has to be worked from the "lid" out rear for the hammer cavity?
Why couldnīt we just as well make that setup attach to the actual hammer?
Such a case scenario in turn itīd be way simpler to fab a collapsable strut rod for the SSG to work from, and this could no doubt be designed into the hammer base. Ie; have the strut rod "disappear" into the actual hammer body.
The actual strut rod in turn then threaded to the hammer rear, and preload to be set per usual. See what iīm getting at here? A collapsable strut rod with pieces that fit each other, just set "dead head" at the max limit. That hole on the hammer the thing threads into in turn would guarantee linearity when collapsed if set up right.
In fact, think hammer spring guide rod here just with a hollowed out and threaded center section, which in turn brings that the actual hammer spring could very well be as long as we see fit, as itīs other end per usual will come to a stop at the bottom of the hammer cavity.

Surely this must have been thought of and done previous?

[rkr]

You can build a SSG anyway you want. The point is to have short free fly for the hammer and a spring held in compression. Alternative is a short stiff spring. BT and Harper slingshot valve are other alternatives but that knocking the hammer thing is problematic with 2mm valve stem. With 2mm stem valve closing force is greatly reduced so your SSG don't have to be as heavy duty as with normal valves. Check the SSG thread for build ideas, there are many ways to do it.

[Racing]

Yeah.
So i thought to myself that before ordering one of them keeerbuuun fajbre bottles.. i wanna check what weīre getting into here right.



Uhu. Got a lathe so spent a wee bit a time turning an adapter from the BSA M14x1.5 to the more generic M18x1.5 all buddy bottles are made on.
Took a ruler to the gun and guestemated what measure was needed to be added to make the bottle NOT run into the stock.
Time ran out though so.. time for trials come tomorrow.

[Racing]

This was no doubt solution to all ills.

Going to snap a few pics, installing it as "close" i did to the stock this thing actually works from a looks point of view too.
As far as capacity..take a guess 

No doubt worth the effort so now for a CF bottle.

[Racing]

Yep. This no doubt works. Setting it as far in vs the stock i could get away with.
Yep.

[Racing]

Last few days here, iīve mostly just used the unit.
Rats ...in as beating that dead proverbial horse.
As such it works very very well and is sure accurate enough, and then some, for the task at hand.

Now.
Probe seal(-s)
The piece is running @ approx 150bar and at that rate toss 25,4īs @ 960 right. Silent in operation too, but then again.. thereīs silent and then thereīs SILENT.
Got a few pcpīs that really are. Where youīd call me a liar as i tell what level of performance the thing is adjusted to, seeing how low key it is.

True, as both me n RKR are in agreement on, is that a slightly larger diameter shroud sure does wonders but that also assumes a well working diffusor.
Have come to play around quite a bit with that there diffusor part and on a whole have to fold as far as FX got it right the first time out. The thing is to keep the through hole on the diffusor as close to caliber as youīll get away with, as this no doubt improves efficiency on the setup (diffusor n shroud).
In turn it comes as no surprise that handing any diffusor so setup filler within just makes the thing even more effective at what itīs there for, suppressing noise.

Ditto then as far as the moderator, keep through holes close to caliber.. yadda yadda...and the truth of it is that it works extremely well. Insanely well even. Yes. "Hollywood silent" truly exists even for 140J guns or whatever, just takes a little getting there.

Now.
All of this of course assumes that the piece isnīt leaking anywhere between the valve exhaust port and the muzzle on the barrel, and again.. it has proven more than once that even stock solution come up short on occasion.
Thus it is ALWAYS a wise move to challenge any given such setup.

The BSAīs are in minority in that they sport a probe mounted breech seal. Of course an o-ring but.. that carries with it a few notes as i see it cause i truly believe i have a SLIGHT leak at said seal.
Reason for this is simple, albeit the 22cal BSA of mine here is VERY well behaved as far as noise it is still "snappier" to the tone/note than say my Reximex Meta or FX Impact. Indeed...
So.
I took to checking that there, why i realized my mistake. Or.. yeah well, read on...
Iīd say the stock chamber for the BSA barrels are roomy to say the least. In turn thereīs a piece of Delrin that kind of acts like a "pre-chamber" (thinking inner diameter here).
As the R-10 is designed as it is the actual "length" spot to hit is rather slim, which is all good as long as you know how to read a ruler or calipers.
However...
The stock o-ring setup iīd say was never designed for any higher horsepower applications, and i absolutely bet thatīs where that "snappiness" stems from.
I friggin KNOW the rings on the transfer port to be on the money, as it turns out the breech one.. not so much.

Said o-ring is set into the probe end on a groove cut for it right, where of course the bottom diameter of said groove will affect how, what and which o-ring will do the job.
Well.
Iīve come to conclude that the actual BREECH is rather much larger in diameter why the groove i cut for the stock o-ring simply doesnīt load up vs the breech walls - thus making for an ever so slightly leak.

Iīll rephrase this different.
I ran an o-ring on 1,5mm thickness... gave that some thought and replaced that with a larger one on 1.78mm.. works just as smooth, gun became more silent.
Checked vs the chrono exit speeds jumped, quite considerably, to approx 980-990fps. So an increase of 20-30fps from this stunt alone.

What iīm saying is that i need to pick the unit apart again and this time out set the whole thing up such that i get an ever so slight load vs the CHAMBER, nevermind the probe.
This, for better for worse, also means that the probe seal will have to be installed where it sits. As itīll "grow" in proportions that rules out making this happen before you install the locking banjo et al. Small price to pay tho me figures.

Iīve touched upon this before, the importance to me of.. you might almost call it stealth wish be. That iīm able to go after the d*mn scaly tails without ANYONE reacting to it, yet alone take offence.
Thus i guess it comes rather natural that iīve come to expect my units to be insanely quiet in operation, fact is i demand them to be.
In short, nevermind the increased muzzle speed and efficiency, to me itīs about turning the piece as quiet as they come.

Guess iīll report back on the matter.. i always do. 

[Racing]

Ok.
So the probe seal deal indeed was a thing. Brazed some material to the groove and recut it, indeed...

That done though, like me n RKR have been over previous, weīve sorts of learned over the yrs that that there thing with shroud diameter becomes more and more essential to keep noise at bay as power goes up.
Indeed the thing has been rather well behaved already where i was at but that being said thereīs of course always room for improvement.

As the stock shroud doubles as a sorts of moderator too that turns these export version R-10īs into something thatīs anything but compact anymore, and seeing that weīre after all talking a mere just shy of 500mm barrel it turns a bit silly really.
At least to my mind.

Of course the alteration of this coupled with the can out front and the larger bottle changes the looks of this thing, but truth be told as if to that being for better or for worse you guys tell me.



This thing is on a full 30mm diameter, leaving that itīs a decent 28mm within. All of a sudden that absolutely massive 60mm dia can out front doesnīt strike me as completely retarded anymore but that being said.. itīs all about performance FIRST right.



As itīs christmas after all i still havenīt had that 300bar carbon fibre bottle delivered, so youīll have to imagine that one. As you can clearly see though that "oh whatīs up with it being that tall" is all gone.
On the contrary, i guess due the more hefty dimensions of things mainly, itīs starting to strike at least me as downright compact?
If nothing else it at least IS different.



Uhu. Might be old news to some but thatīs how the thing sits. In other words thereīs STILL room to spare, now seeing that the shroud is on a full 30mm and the bottle a full 60mm.
I believe the CF bottle to show is on 61.. so no harm no foul.

On a whole the exhaust note of course changed. Thatīs to be expected, why itīs now more of a "thud" or "thump" if you wish. That snappiness is all gone and the exhaust note is no doubt more mellow and WAY lower in frequenzy.
Happy with that. Have to say.

Another thing i did as i had the thing apart this time out was to hand the barrel a real "deep clean" and did it EVER hold some dirt! As thereīs no o-ring to damage i went at it with a bronze brush n cleaner, followed by patches n cleaner.. then patches all dry.. thing was like it was never to turn clean!
It finally did though, happy with that too as it hands a fresh platform to start from.

Now to check things like ES and SD to evaluate the reg on there. Still the stock unit, just with polished belleville washers and what have you.
I reason as such that beyond 20fps ES.. and that thing is outta there..

[Racing]

Ok.
So the probe seal deal indeed was a thing. Brazed some material to the groove and recut it, indeed...

That done though, like me n RKR have been over previous, weīve sorts of learned over the yrs that that there thing with shroud diameter becomes more and more essential to keep noise at bay as power goes up.
Indeed the thing has been rather well behaved already where i was at but that being said thereīs of course always room for improvement.

As the stock shroud doubles as a sorts of moderator too that turns these export version R-10īs into something thatīs anything but compact anymore, and seeing that weīre after all talking a mere just shy of 500mm barrel it turns a bit silly really.
At least to my mind.

Of course the alteration of this coupled with the can out front and the larger bottle changes the looks of this thing, but truth be told as if to that being for better or for worse you guys tell me.



This thing is on a full 30mm diameter, leaving that itīs a decent 28mm within. All of a sudden that absolutely massive 60mm dia can out front doesnīt strike me as completely retarded anymore but that being said.. itīs all about performance FIRST right.



As itīs christmas after all i still havenīt had that 300bar carbon fibre bottle delivered, so youīll have to imagine that one. As you can clearly see though that "oh whatīs up with it being that tall" is all gone.
On the contrary, i guess due the more hefty dimensions of things mainly, itīs starting to strike at least me as downright compact?
If nothing else it at least IS different.



Uhu. Might be old news to some but thatīs how the thing sits. In other words thereīs STILL room to spare, now seeing that the shroud is on a full 30mm and the bottle a full 60mm.
I believe the CF bottle to show is on 61.. so no harm no foul.

On a whole the exhaust note of course changed. Thatīs to be expected, why itīs now more of a "thud" or "thump" if you wish. That snappiness is all gone and the exhaust note is no doubt more mellow and WAY lower in frequenzy.
Happy with that. Have to say.

Another thing i did as i had the thing apart this time out was to hand the barrel a real "deep clean" and did it EVER hold some dirt! As thereīs no o-ring to damage i went at it with a bronze brush n cleaner, followed by patches n cleaner.. then patches all dry.. thing was like it was never to turn clean!
It finally did though, happy with that too as it hands a fresh platform to start from.

Now to check things like ES and SD to evaluate the reg on there. Still the stock unit, just with polished belleville washers and what have you.
I reason as such that beyond 20fps ES.. and that thing is outta there..

[rkr]

That looks good with larger shroud in there. I haven't bothered making my high power guns super quiet anymore as I only shoot them at range. It was fun though with .357 Evanix and steel black powder silhouettes, only kling klangs of silhouettes falling was heard when shooting that gun.

Have you checked the accuracy after you cleaned up the barrel? I have a feeling that it might take some re-leading for slugs and BSA barrels to shoot accurately again. Usually my slug shooters work good after proper clean but on occasions it'll take closer to 100 shots to get it accurate again and that's typical with rough barrels like BSAs.

[Racing]

First up...
Thank you SO much for your support, knowledge n ideas as far as this unit RKR.
Second up, HAPPY NEW YEARS! 

That out of the way.. LOL
Noise IS a consideration in my case and as iīve touched upon previously sound is my job. I wonīt get down that rabbit hole again here n now but let it suffice to say that thereīs TONS more to be had vs the store bought stuff, and thatīs just the way it is.
Then again, calling this R-10 super high power would be pushing it... Again. A dedicated long range ratter, thatīs it.

No.
I havenīt fired a single shot out of it since this last episode.
Fact is, i came across something that just happend to be of the right dimensions and i bet iīm just goin Don Quiote here but.. wanna try it for size - and thatīs an X ring to seal the chamber.

As the probe nose unbolts itīs fairly easy to pull alterations to it, and as weīre basically just talking one groove just of varying dimensions depending on the seal used.. why the *ell not?

So yeah. I recut that thing to take an X-ring intended for an Impact, at least believe it is as i found it in an FX ziplock bag.
In turn i made way more sure the probe end was linear vs the probe body, which iīd say is a must seeing the X-ring.
Havenīt tried it as of yet, thereīs a few small other quirks i want to look into too before ready but.. It chambers rather well. Ends up where it should - and so forth.
In short it all looks rather promising, and it sure gets in there with an ever so slight interference fit for the win iīd say.

Iīll report back asap, first upīs new years though... 

[Racing]

Right.
So the unit is up and running again, performing to whatīs to be expected iīd say... and then some actually.

As for the use of an X-ring, well the chrono lever lies me thinks why.... *drumroll*...in practice it netted about zero really.

Iīve tried this last probe setup (read - probe seal) now using both X-ring as regular o-rings. A few insights on the matter iīd state is in order.. no doubt.
First up, that there with o-ring grooves sometimes is a bit more to take in than most believe, or even care about, i bet. A o-ring, seeing "our" applications, should never see a groove where the seal "goes tight" vs its groove.
Ie; an o or x ring that sports say 1.78mm material thickness can very well be installed into a 2mm wide groove. I tend to hand the seals and "end shake" around the 1/10mm mark or so. What i do is just grind HSS cutter steel to fit and take it from there. Something see.. to have a few lathes around is a wonderful thing 

So chrono readings were about the same regardless if X or O ring. Might be the X-ring setup came to net a few fps but for sure not a difference appreciable enough to care about. Write it off as standard deviation if you wish.

However iīd state that the X-ring install is more "static" in as much that as either of the two rings are shoved into the breech they WILL compress, which is a desireable in this case i think.
That in practical terms boils down to that the X-ring (to those not in the loop, X-ring is sorts of like a square o-ring in essence), per default, will sport two "major diameters" when compressed where the regular o-ring will see only one.
But.
The prime question here, at least as i regard it, is if thereīs any appreciable performance differences between the two, in other words if the one seals better than the other for the application at hand, and on that one.. nope.
Caveat here is that it MIGHT be a different matter for differing loads.
Ie; i run them Knockout slugs just a smidge over 1000fps as is. It might very well be that any performance difference might come into effect as i use say 34 grain slugs @ the same muzzle speed?
But for now, where iīm set.. nope.

That i HAD a minor leak at the breech though is just to resign to. Exhaust note as well as amplitude (read - dB) had no doubt changed since i got this here with the probe seal handled.
The in turn now implement of that larger diameter shroud stuffed with filler... in turn coupled with a diffusor on a tighter through hole, that of course cuts down on the job the actual moderator has to do.
In simpler terms, the current setup is more effective at what it does. The gun has turned more quiet in use in short.

So far i havenīt gotten around to sight the thing in yet, hope to adress that come tomorrow. In other words as of yet no idea how this new shroud n moderator setup affects accuracy - if at all.

However.
This playing around with numbers on the R-10 has brought up what in reality is a few question marks to me.
I have a hard time taking to heart why the barrel breech and the adjacent delrin "spacer" ahead of the barrel where it sits is cut on 6mm flat while the probe is on a mere 5,5mm.
No. Itīs true this "mismatch" wonīt amount to all that much for say a 12fpe gun (as nor will the dreaded R-10 bolt flip fr that matter). Truth be told not for a 34J piece either. However, at this current performance point weīre rather ahead of any of those performance levels mentioned why...

See. We know the probe on these units CAN leave some to be desired for "modern" use (read - increased performance levels). Why BSA even spent the time needed on putting what i presume is nickel on the probe.. thatīs just beyond me. But... whatever.

This 5.5mm idea makes that for the app reduced diameter happen as far as the through hole on the banjo "lock" fitting too.
As the breech, on a whole, is on 6.00mm.. as we get into elevated levels of performance (say CAPACITY of inxs of 100J/74fpe) at least I normally reason way different and will find ways to support the seal as best as i can. Any seal really. Especially so a "dynamic" seal tho, as a breech seal for instance.
As we rely on some sort of rubber ring to hand what we crave n need it is always a good idea to support said seal as best as we can why at least I would have found it reasonable to see a probe dia of say 5,85mm.
I know.. i know, to most the difference might strike one as slim, 5.5mm vs 5.85mm, but from a practical standpoint i can assure you it is anything BUT.

All pcpīs leak. Of course they do, why the modus operandi here as far as iīm concerned is to minimize this leak percentage as best as we can.
This is where minor differences like the one above comes into play, and YES it does make for a difference.
Cause it works like this, the pressure at hand is what MAKES the o-ring run up/gets forced vs the areas/walls of the groove and seal. In other words effects like seal expansion due pressure comes into play as well, but asking a 5.5mm outer dia ring to expand 0,6mm or more (for an interference fit under load) in the milliseconds applicable here.. That can turn into a tall order why attention to these "little things" can make for a rather large difference in performance. Especially so when we start to sum them all up.
This of course holds true for transfer tube seals and what have you too (where so fitted).

Anyways. Unit is no doubt performing along expectations finally. Itīs reasonably quiet in operation, it hands reasonable amounts of power for the task at hand and in the end at least up until now have handed accuracy all i can ask - again seeing task at hand.

In other words as of today i guess time has come to start n try tune the thing for optimum performance (accuracy).
Iīve been giving that there with choice of pill some more in depth afterthought and truth be told iīd say using them 25,4īs running somewhere around the 1000 mark, if 950 or 1050 i really donīt care which, is where iīm at.
Them Knockouts are available like.. everywhere. Doesnīt cost a fortune and obviously performs rather well. Thus far at least.

Do i feel itīd be an idea to at least try that 650mm barrel option iīve got laying around?
As of right now?
No. Not really. Again, the thing does what i ask of it and rather well at that. Upcoming? Might very well be..

So a few things then.
The carbon fibre bottle of course, when it shows. In turn iīm giving thought to go grab me a kit of materials needed to be able to powder coat any and all parts i make happen. Flat black should do it..
Just an old whatever oven. Has to be large enough to take a shroud and so forth tho.
Then the deal of the infamous R-10 reg. Going to keep a close n keen eye on what the chrono tells for the closest up time here. Need be i wonīt even be bothered noodling around with the stock piece, iīll just replace it. If a Huma or Carls "big bore" version, to be honest they both have a decent rep so.. whatever kind a.

Nah.
Iīll revisit this on here, iīm sure.
Next project up though is an old Hatsan BT-65 in 22cal that came in the door...

So for now.. just enjoy and use this old warhorse. It has no doubt come a long way.

[Racing]

Update then.

Yep. Have been using and enjoying the thing - hardcore.
Rats, for obvious reasons i guess, seems to truly hate the thing  !

Then the other day, problems.. no fire, and i ran around like a one legged chicken there for a while.
In the end ripped the unit apart and saw something for the first time..

I run a fairly stiff return spring for the poppet on this thing and what had happend was that that 1.8mm dia shank i use to set the poppet seal had worked itself deep into that poppet seal material and cracked it! 

Ok.
So redid the entire thing to 2mm instead, made an entirely fresh poppet for it and let her rip. Came to lower reg pressure slightly (now on just shy of 150) which again handed me approx 960 using the JSB Knockouts.
As stated earlier, happy with that seeing how commonly available them Knockouts are and as the gun doesnīt seem to care what diameter Knockouts.. all good.

Anyways.
Unit is of course back together and as such performing per previous. As to why that thing cracked (a first to me, and have done quite a few such conversions by now - gathering thousands of firings by now) i have absolutely no idea. Might be that the shank didnīt have its end dressed well enough maybe?

[rkr]

I had the same problem with my first 2mm valve stem, I've been using set screws at the rear of the poppet since. Use at least M4, M3 gets stripped at least on larger diameter poppets.

20211016_173021 by abbababbaccc, on Flickr

As an alternative I used a hybrid 2mm/3.2mm stem in my .172 BSA. It had big enough valve tunnel with stock stem but I wanted more dwell so this was an easy way of doing it.

2023-05-08_05-57-37 by abbababbaccc, on Flickr

[Racing]

So have I, and FWIW to be noted this does increase poppet weight slightly.

TBH and blunt though iīve done a fair share of these 2mm setups by now and this is the first time iīve encountered an issue. At all.
To be noted is that the BSA was actually on a 1.8mm shank as this happend.
Have redone to 2mm flat since.