Tuning FX Barrel liner-to glue or not to glue

Definitely understand bigHun as I am a tinkerer but my tinkering has been the need for speed. For me, again me, it just didn't make sense to try and adjist when all shots are touching at 50yards. Now I did just order the harmonic tuner to see if that will do anything for my groups at 75 yards. I really don't see hunting out past that range with my rifles although I know I can. 
 
About 18 mo ago I put a CF sleeve on the liner which came with my MkII bought new in May 2020. I glued it per instructions. Dry fit on the liner was not tight; I could rotate the liner in the CF sleeve. Liner was indexed and was gratifyingly accurate before the sleeve. After sleeving accuracy was worse. Fit of the CF sleeve in the barrel kit metal sleeve was not tight. I tried a lot of things, re-indexing (indexing hadn't really changed), varying jam nut tension, cleaning, re-tune, add o-rings to tighten the fit of the sleeve to the outer metal sleeve, etc and nothing helped. Gave up. This liner had shot both slugs and pellets well with the right tune. 

I don't doubt that others have gotten improvement from sleeves, but I will never put another one on a liner which is working well, and certainly would thoroughly try it unglued first.
 
If you place the orings evenly then do you notice any difference between them and CF sleeve?

I feel it easy to tune the gun when the barrel is mire rigid.

Tuning for extreme accuracy with O rings on the liner takes much more time and concentration. 

A rigid barrel has less flip during firing that causes it easy to tune.

My BSA solid barrel is the most easy to tune being the most rigid as I understand. 

The latest improvement of barrel tensioner also 2nds the same.

Bhaur
 
re: the joys of the hype, the barrels are not straight, cold hard fact. There are three types of fit, slip i.e. loose it can be .001" or greater, interference .0005" or press fit. The issue is because you are playing with things that aren't straight to begin with you are hard pressed to tell for sure. The VERY first few inches will tell you quickly which you are blessed with. All that said, I've got 2 Mavericks, 3 barrels 2, .25 and 1 .22, tried the .25.s unglued, good accuracy, some POI change initially. Then I glued them/ epoxy...note use THIN Epoxy, your life will be simpler. Tested the results after a 24 hr cure. POI changed, no noticeable difference in results at 30 yards(I'm not shooting from a full rest so results are variable)(all tests are with pellets only) Swapped out to the .22, unglued, 28 rounds dime size hole, rested, after some very frustrating tuning. IMHO, if you have a sloppy fit, glue it, if it's a nice snug fit, save your time. If gluing use expoxy, it must chemically cure, air curing is impossible as...there is no air in the middle.

I'm GUESSING that the most benefit comes when using higher pressures and heaver larger pellets. Another cool test would be to see how much flex there is in the barrels as the pellet and air travel through the thin barrels.

Now what FX should do is provide a straightened barrel that is carbon fiber wrapped. You can straighten your own barrel but...it requires a large FLAT surface, i.e. a surface plate v-blocks and .001 dial indicators, and a ton of patience. Because the barrels are not round due to their manufacturing process.
 
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Carbon fiber liner sleeve??!! What??!! I thought when all this talk about gluing the liner came out it was about gluing the liner to the outer barrel! I went thru two large tubes of the industrial grade JB weld, and almost clogged up my transfer port!

I had to shoot the JBweld out. Took a mag and a half of pellets! But I’m good now! I left the o rings in there to help keep the liner centered within the barrel tube, and also had to drill out my moderator to .357 cause my 22 cal pellets started clipping.

Now what’s this carbon fiber liner sleeve again? What’s it for? I didn’t spend no $35!
 
Carbon fiber liner sleeve??!! What??!! I thought when all this talk about gluing the liner came out it was about gluing the liner to the outer barrel! I went thru two large tubes of the industrial grade JB weld, and almost clogged up my transfer port!

I had to shoot the JBweld out. Took a mag and a half of pellets! But I’m good now! I left the o rings in there to help keep the liner centered within the barrel tube, and also had to drill out my moderator to .357 cause my 22 cal pellets started clipping.

Now what’s this carbon fiber liner sleeve again? What’s it for? I didn’t spend no $35!
Me thinks you might have been better off with the liner, just say'n. I did mess up and get a tiny of JB in the barrel, luckily I had acetone, gave it a good swabbing and dodged a pellet so to speak.
 
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fx users spend a lot of time and money straightening and stiffening barrels. How much will the gun end up costing?
If you have to ask, you can't afford it. :unsure: Adding a CF sleeve is $35, plus shipping and tax and some THIN EPOXY. Yeah, it's a bottomless rabbit hole. I simplify the entire thing as 'I can't take it with me so...."
 
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fx users spend a lot of time and money straightening and stiffening barrels. How much will the gun end up costing?

Silly rabbit, If the barrel is straightened out then how does it shoot around the corner?

Plus who leaves their toys alone?
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Ha ha! I was a joshin’ about filling my outer barrel with epoxy. I’m a big fan of the carbon fiber sleeves and have always epoxy’d them onto the liner. Been doing it since day one. I was one of Ernest’s test pilots on this system when he first came out with them

That thought has crossed mind also but couldn’t commit to it. With the carbon sleeve only, the gun shoots awesome so not sure there is that much to gain with that sort of commitment. LOL
 
As much as I use epoxy, my wife probably thinks I have some sort of shady business arrangement with one of the big name chemical conglomerates. But for bonding a carbon-fiber sleeve to a barrel, a bearing compound like Loctite 638 sacrifices nothing and is much easier to use. Granted epoxy is the way to go if the parts are a loose fit but Loctite 638 is good for gaps up to 0.010" (i.e. a 0.020" difference on the diameter) which is usually more than enough for this type of job.
 
As much as I use epoxy, my wife probably thinks I have some sort of shady business arrangement with one of the big name chemical conglomerates. But for bonding a carbon-fiber sleeve to a barrel, a bearing compound like Loctite 638 sacrifices nothing and is much easier to use. Granted epoxy is the way to go if the parts are a loose fit but Loctite 638 is good for gaps up to 0.010" (i.e. a 0.020" difference on the diameter) which is usually more than enough for this type of job.
is it air cured?