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.If Mr Fredrik said no POI or because user error....Make me wonder why FX? made stiffener & barrel tensioner kit?!?!
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.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?
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.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 understand that if the air pressure inside the liner and outside the liner would be same, the liner would not be affected.All will be well if the thin liners in the high pressure cylinders do not start to flatten
Very convincing pointsAre 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)
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.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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In the machine shop we had a saying.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!
I often wondered why they don’t hold the barrel via a pinch clamping arrangement.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 .