FX Lock this thread please- Discussed with Fredrik, there is no evidence of POI shift in FX barrel liner system

If Mr Fredrik said no POI or because user error....Make me wonder why FX? made stiffener & barrel tensioner kit?!?!
Income perhaps/probibly. Both of my guns do have CF sleeves, one glued, one not, I forget which is which. I want to say they helped but I put them on before I got things dialed in so can't say for sure and it's been over a year.
 
I bought the Barrel Tuner, because of a hype in many previous threads like this ... shot couple thousand and realized that tuning the MK2 to very last 95% is more finicky then I wanted to go that far.
I bought the Larger Plenum upgrade kit, because of a hype in many previous threads like this ... shot couple thousand and realized that if I am not going to a larger then .25 caliber the extra power is useless in my case. But the expense was done...
I installed the CF sleeves on the liner because of a hype in many previous threads like this ... shot couple thousand and realized no F improvement (thanks G I didn't bond them). Removed the CF sleeves and put back the orings.
I bought the Barrel tensioner, because of a hype in many previous threads like this ... shot couple thousand and realized no F improvement. Removed the tensioner and put back my barrel tuner. And invested the rest of my time to finish the tune.
What else did I?
Oh yes, I was tinkering about the backbone plate, but didn't like any of the designed.

So, pretty much comes down to a fact, that if you throw enough sheit on a wall something will stick to it.
We all know what this hobby is... we are either impulse buyers, or ... addicted to shopping.
Why that would be Frederics fault if he can make couple bucks here and there.

And btw, I am shooting 50-100 meter rings only no hunting, and I don't have incidental POI shifts, and no first couple cold Reg shots. My guns are all in a hard case, no digs no scratching, I am taking well care of my toys.
 
Yes but I agree to the point that the choke fixes all inconsistency issues of rest of the barrel. I understand that FX liner cannot be unchoked and still accurate. Am I right?
I have cut the chokes off a few 600’s and made them 500mm. Why? Harmonics. Let’s just say after so much testing, I couldn’t even stand the thought of shooting an Impact for a month. Testing proved I could get decent accuracy, but the choked standard and heavy had an edge. I read once where someone said that Dubber dude stated no choke, no hope. He’s a metal straw guy so he speaketh the truth. Two of my M3’s wear real barrels now. Why? Because a fowling or tiny lead streak choke barrel can be as accurate as a real unchoked barrel, but not as consistent. I’ve been saying for years, most POI shifting issues are more choke related than flimsy barrel related. Most but not all. If you are a pellet FX guy and have POI issues, as long as you don’t have a bad liner with a lead file for a choke, it can be fixed without buying any do dads for the barrel system. Your gun is assembled on a bind or you need to dot all your I’s and cross all your T’s when you assemble all the barrel parts. Interesting topic here for a change. I need to read more of it after your post I quoted.
 
Don't you think it's the way the barrel is kept in the action that makes POI shifting occur ? Tiny grub screws to hold a 500 , 600 or 700 mmm assembly in place , that's a lot of cantilever .
Yes it may be one of the factors but now FX M3 has a barrel holder that has two additional screws. So now three screws hold the barrel.
 
Are the POI shifts random, including left/right? If they are mainly up and down, perhaps velocity variation is more of a factor. Or as Fredrik said, lead build-up in the liner. But, but, but - see the last paragraph below.

If the shifts are in any direction, that sounds like the barrel pointing somewhere else each time the shroud is bumped.

Note that the trio of South African pest shooting video makers check the zero of their FX PCPs every time they transport their airguns to the farm or hunting field. That is good practice, but suggests a known potential for drift between shooting sessions. Sure, zero checks are standard practice for safaris after international flights, but are they required if no one but you handled your guns?

If an airgun was shooting well at the end of your last session, lead build-up causing fliers seems less likely at the start of the next session. So, are some airguns so fragile that traveling on asphalt roads in a padded case for 20 minutes is likely to lose zero? (I know where two of those SA guys live, and the farms they shoot at, because I attended the local high school there, 44 years ago)
 
Are the POI shifts random, including left/right? If they are mainly up and down, perhaps velocity variation is more of a factor. Or as Fredrik said, lead build-up in the liner. But, but, but - see the last paragraph below.

If the shifts are in any direction, that sounds like the barrel pointing somewhere else each time the shroud is bumped.

Note that the trio of South African pest shooting video makers check the zero of their FX PCPs every time they transport their airguns to the farm or hunting field. That is good practice, but suggests a known potential for drift between shooting sessions. Sure, zero checks are standard practice for safaris after international flights, but are they required if no one but you handled your guns?

If an airgun was shooting well at the end of your last session, lead build-up causing fliers seems less likely at the start of the next session. So, are some airguns so fragile that traveling on asphalt roads in a padded case for 20 minutes is likely to lose zero? (I know where two of those SA guys live, and the farms they shoot at, because I attended the local high school there, 44 years ago)
Very convincing points 👍
 
I have a custom RAW that Allen Zasadney did for me, it was originally a .35 caliber and he converted it into a .22 by putting a FX Superior barrel liner in.
He beds the liners in epoxy and they become one with the barrel.
It is very accurate and no POI issues so far.
He absolutely loves the FX liners and is having spectacular success with them.
He’s doing a custom Steyr LP for me and it too will have a FX superior liner epoxied into the prepared barrel.
This has been an interesting thread!

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I have a custom RAW that Allen Zasadney did for me, it was originally a .35 caliber and he converted it into a .22 by putting a FX Superior barrel liner in.
He beds the liners in epoxy and they become one with the barrel.
It is very accurate and no POI issues so far.
He absolutely loves the FX liners and is having spectacular success with them.
He’s doing a custom Steyr LP for me and it too will have a FX superior liner epoxied into the prepared barrel.
This has been an interesting thread!

View attachment 429054
I too love FX liners as far as accuracy is concerned. I understand that as you have explained, if the liner is epoxied inside a thick carbon fiber tube or metallic tube, it is very successful.

The matter is same that when the liner is in fragile position like I side FX barrel housing, it can move a bit while if we glue it and make it sturdy, it becomes very good. Further the free floating barrel system of RAW is very convincing.

I have read that not only AZ but many other tuners also use FX liners which reflects their liking of these liners.

Off course these liners shoot great if properly secured.

I have myself installed FX liners on Daystate Delta Wolf and achieved great accuracy at bench.

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I get a very slight poi shift after every fill. But after two shots it is spot on again.
With a digital gauge on my 2nd reg I've noticed that after the fill my second reg is a bit higher than I want, after the second shot it's a bit lower than I want, from there on out it's spot on.
If I shoot until I need a refill, refill and then shoot right away this doesn't happen. So to me this means the reg sticks after sitting for a length of time.
 
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Tell them what they want to hear,sell them what they think they need.
If something can be made better at the time ,and it isn't,then it was not made right!:unsure:
In the machine shop we had a saying.
If you made it, and it’s wrong, you made it wrong.
 
Don't you think it's the way the barrel is kept in the action that makes POI shifting occur ? Tiny grub screws to hold a 500 , 600 or 700 mmm assembly in place , that's a lot of cantilever .
I often wondered why they don’t hold the barrel via a pinch clamping arrangement.
A pinch clamp is like the shaft collar shown in picture, except the receiver is split at 12 o’clock and two or three socket head cap screws cause the barrel to be gripped 360°.

IMG_1841.jpeg
 
In the machine shop we had a saying.
If you made it, and it’s wrong, you made it wrong.

If you made it to print, you made it to spec; even if that is wrong.
I often wondered why they don’t hold the barrel via a pinch clamping arrangement.
A pinch clamp is like the shaft collar shown in picture, except the receiver is split at 12 o’clock and two or three socket head cap screws cause the barrel to be gripped 360°.

View attachment 429085

Because the pellet distortion caused by over tightening the barrel retention grub screws, dimpling the barrel through to the bore, will be nulled out by a tight choke :)
 
Here is my question everyone always talks about about a poi shift how much of a shift is it I never experienced it I was running cf liner but the 2 guys shooting impacts were are only using orings and haven't noticed it either so poi are we talking a inch plus or under that at say 50 yards
Do you mean that 1" shift at 50 yards is OK ?
 
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