How many have killed a PCP trying to tune power?

PCPJuicer

New Member
Ever tried to scale up an OEM air tight interface between internal components???

The thought was scale up everything equally from the valve (hole ID for air transfer tube), OD of air transfer tube and o ring that seals the joint.

Obviously I was extra careful to ensure the same relative stretch/compression of sealing o ring was the same as standard conditions when factory assembled. It took me some time to pluck the courage up to cut some metal.... If this concept failed..... the Logun was toast 🙊.

Typically the whole idea failed, at this point I have only shot 3 pellets out of the thing....I'm sure I do not need to explain my mindset @ this point!!!

Anyway, I'll get tote point. Logun will have spent countless hours & £££ designing, testing and developing the design conditions of this interface to its optimum. Not looking good for my rifle though.... I have no plans to mass produce and therefore no time or budget available to fine tune the design to fix my new ornament.

The stuff seen in below link is your friend.... Be precise enough ensure a maximum gap of 0.5mm between components, this stuff will seal the joint up to a pressure of 3000psi 😍😍😍.

The upgrade has changed the strip down and re-assembly process. 3 pieces that would normally separate are now considered 1 part and other parts have required modifications to allow clearance for assembly to be possible.

But.... I have since serviced the thing 4 maybe 5 times since and the joint is still as good as the day after I bonded the components together.

I had intended to do a write up/detailed guide with pics, after the time and effort this has just taken I'm glad I never started lol. Just felt many more could benefit from this miracle liquid, you will just have to figure out if your rifles internals will feasibly allow a tune up using this scale up approach (NOT FOR THE FAINT HEARTED).
What you do with this info is your bongos and I take no responsibility for anyone trying to tune for more power and in doing so wrecking their rifle. If this terribly written post is leaving you wondering "what the hell is this guy talking about?" ..... Put your rifle and tools down, TRUST ME.

 
My PCP goes back to the Airgun centre every year for a full service - never had a problem and bang on poundage - simples
all air rifles are made as they should operate - why change it. ????

my thoughts would be to change it rather than mess around with something that works correctly but not to your requirements
 
Simply because it's hard enough to find a sweet 16 these days as it is.....let alone the xs....Which essentially is what it has become aside from the additional mods for assembly the internals mimic the xs where feasible.

The s16xs is an iconic air rifle....I wanted one and couldn't find one....so I made one from a cheap neglected old s16s that was sold as spares or repair, potentially saving it from the tip.

I posted the info help others....not to be heckled because you THINK it was probably better before hand....I know it's better now
 
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Ever tried to scale up an OEM air tight interface between internal components???

The thought was scale up everything equally from the valve (hole ID for air transfer tube), OD of air transfer tube and o ring that seals the joint.

Obviously I was extra careful to ensure the same relative stretch/compression of sealing o ring was the same as standard conditions when factory assembled. It took me some time to pluck the courage up to cut some metal.... If this concept failed..... the Logun was toast 🙊.

Typically the whole idea failed, at this point I have only shot 3 pellets out of the thing....I'm sure I do not need to explain my mindset @ this point!!!

Anyway, I'll get tote point. Logun will have spent countless hours & £££ designing, testing and developing the design conditions of this interface to its optimum. Not looking good for my rifle though.... I have no plans to mass produce and therefore no time or budget available to fine tune the design to fix my new ornament.

The stuff seen in below link is your friend.... Be precise enough ensure a maximum gap of 0.5mm between components, this stuff will seal the joint up to a pressure of 3000psi 😍😍😍.

The upgrade has changed the strip down and re-assembly process. 3 pieces that would normally separate are now considered 1 part and other parts have required modifications to allow clearance for assembly to be possible.

But.... I have since serviced the thing 4 maybe 5 times since and the joint is still as good as the day after I bonded the components together.

I had intended to do a write up/detailed guide with pics, after the time and effort this has just taken I'm glad I never started lol. Just felt many more could benefit from this miracle liquid, you will just have to figure out if your rifles internals will feasibly allow a tune up using this scale up approach (NOT FOR THE FAINT HEARTED).
What you do with this info is your bongos and I take no responsibility for anyone trying to tune for more power and in doing so wrecking their rifle. If this terribly written post is leaving you wondering "what the hell is this guy talking about?" ..... Put your rifle and tools down, TRUST ME.


I think I need an Enigma machine for this one.

Tim
 
Arr the Sweet 16 - fond memories of mine as I got my first permission some 25 years ago using it. Went from a handful of rats from the cow shed using my TX200 to nights of fifty plus due to how quickly I could reload - it was a revelation.

Still got it some 25 years later, recently serviced by the Loganator and it’s as sweet as the day I bought it. Sadly doesn’t get much action these days, bar being used as a training rifle for the kids.

I would suggest doing a google search and contacting the Loganator - what he doesn’t know about them is not worth knowing.

OMG - I look so young and thin in that photo :lol:
 

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S16 was a piece of junk to begin with. And trying to tune one was a recipe for disaster anyway as the build quality was never great.
There are plenty very tunable pcp's (Falcon) Loguns (Webley) were never one.
 
Had a friend turn up with an FX impact the other day for a play around, an FAC rifle, and it’s genuinely impressive with how it was grouping at 100yards and how hard it was hitting.

but they aren’t cheap and I’m not sure there’s much need over a 22LR and a 12 ft-lbs pcp.

regards.
Gixer
 
Had a friend turn up with an FX impact the other day for a play around, an FAC rifle, and it’s genuinely impressive with how it was grouping at 100yards and how hard it was hitting.

but they aren’t cheap and I’m not sure there’s much need over a 22LR and a 12 ft-lbs pcp.

regards.
Gixer
I think that the FAC Airgun’s fit is in the 40ft lbs range. Where 12 is not quite enough and 22 shorts don’t work through your rifle or are just hard work to get hold of.
The downside is the expense of them particularly a PCP and tank etc, the hassle of filling said tank. The fact that you lose so much money on one if bought new, the secondhand market is very much a niche one for FAC Airgun’s. As you have pointed out a 12ft lbs and a .22lr cover most things.
 
Rambling and poorly punctuated tosh about destroying a worn out old air rifle.
I'm sure this isn't what you want to hear and obviously I haven't seen your 'impressive' work, but from my perspective you haven't 'tuned' it, you've just broken it.

I suppose I should ask if you bothered to chronograph it before or after to see if your 'improvements' did anything, but from your write up, I suspect I know the answer. I could also ask if you've registered it as an FAC rifle if you did indeed manage to increase the ft/lb, but I fear I might know the answer to that as well.

For my part, I'm very, very sceptical that what you've done has improved power, consistency, reliability or precision in any way. As you say, the manufacturer will have spent a lot of time, energy and expertise to get the design working as well as it possibly can, then spent even more time manufacturing it to high tolerances. That being the case you'll forgive me if I'm less than confident in your ability to better them, especially through arbitrarily widening carefully optimised air transfer ports and then gluing precision machined, high pressure bearing parts together with plastic cylinder sleeve retainer.

Anyhow, I'm glad you've ben able to bodge the bits you broke back together and I sincerly hope that the seals continue to hold up for the foreseeable. Please never try and sell this rifle on, and if you do, please, please make it very clear what you've done and what the implications of that might be to the new owner.

Oh, and welcome to the SD.

Alistair.
 
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