Carbon fiber sleeve accuracy vs carbon fiber sleeve + custom spacers?

For those that have added a CF sleeve over the barrels for better accuracy, what is your experience with adding custom spacers to the mix and did it add more accuracy to the CF sleeve already added?

In the passed all that was done was to just add the CF tube and be done with it but now with the new 3D spacers did your accuracy significantly go up or just a tiny bit or not at all?

Thanks

Dan

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Hmmm. This is a bit confusing. And possibly misleading....

So, there is the superlight barrel system which is specifically what these spacers are intended for. On mine, I cut the sleeve and epoxied it on both sides of a spacer toward the middle (normal factory spacer) then put another spacer toward the tip where I left maybe an inch of the liner bare. 

A superlight barrel uses a jamb nut close to the receiver to retain the liner. The other type of barrel system seen on other fx guns and older crown barrels uses a steel tube that the liner slides into. The liner is retained by a hollow bolt toward the muzzle end of the steel liner tube. The carbon sleeve is intended specifically for this type of barrel system and slides inside of the steel tube. 

Obviously it can be used on the superlight barrel, but this is what these spacers are intended for. So, I'm struggling to understand how the sleeve would be used at all with no spacers...? 
 
I recently added two of these to my 500mm Crown barrel. Before adding them, I had one factory spacer on the last 3/4” not covered by the carbon tube, and one poorly bored out factory spacer at the midpoint. I didn’t like that setup, the gun was accurate, but I felt that it wasn’t exactly rigid or secure enough and always left some doubt in my brain. With these new spacers, the interface with the CF tube is much larger and more secure. The o-rings I used, that interface the shroud are very tight, and a bear to get past the threads, but leave no doubt in their fit. Is it better and more accurate? I truly don’t know yet, as the wind hasn’t allowed a real test. It certainly isn’t worse, as I was hitting my 1-1/4” spinners at 97 yards easily and consistently last night. For me, it’s better because it has removed any doubt in my mind about the barrel/shroud integrity, and I was never a fan of the factory spacers. 
 
I recently added two of these to my 500mm Crown barrel. Before adding them, I had one factory spacer on the last 3/4” not covered by the carbon tube, and one poorly bored out factory spacer at the midpoint. I didn’t like that setup, the gun was accurate, but I felt that it wasn’t exactly rigid or secure enough and always left some doubt in my brain. With these new spacers, the interface with the CF tube is much larger and more secure. The o-rings I used, that interface the shroud are very tight, and a bear to get past the threads, but leave no doubt in their fit. Is it better and more accurate? I truly don’t know yet, as the wind hasn’t allowed a real test. It certainly isn’t worse, as I was hitting my 1-1/4” spinners at 97 yards easily and consistently last night. For me, it’s better because it has removed any doubt in my mind about the barrel/shroud integrity, and I was never a fan of the factory spacers.

Thank you for your insight Scotty
 
I'm thinking of adding a CF tube and maybe spacers to a 50 cal, need to see how it shoots first, but the barrel is very thin. I think at the very least, a CF reinforcement will be beneficial, not sure about the spacers, but maybe.



The CF tube and spacers will definitely change the harmonics, and that change can be good or bad. In theory it will allow the projectile to leave the barrel before the barrel has time to flex, and should allow for more accurate shot placement. The spacers help spread this load out to the shroud for more reinforcement.
 
Not confusing to qball, and he understood the Q&A and simply what's the difference in accuracy btw the 2 on a Crown, Maverick or ....




pretty hard question to begin with with even harder process to get any “conclusive” answer. like I said the difference could be quite minimal and also the difference might not show up during test conditions mainly thermal induced interface tension both hot and cold.


my personal opinion is less spacers the better. At the end of the day we all know a free floating barrel is best but how to archive that with a FX barrel that requires minimum 2 parts? The 2 parts being the barrel/liner and the shroud with spacers as interface in the superlite system or the liner, barrel using spacers and jam nut as interface plus possibly a shroud plus possible tensioning system for STX. No matter how you look at it there are multiple variables.


My approach always has been eliminate as many variables as possible. I did add a carbon liner to my superlite barrel but I use only 1 factory spacer at the end only to line up the muzzle with the exit of the shroud. This in my opinion will best imitate a free floating barrel or act like a free floating barrel with some weight at the end like a moderator. If multiple spacers are added in the middle then the barrel/harmonics will interfered at multiple locations along the barrel plus they aren’t fixed so simply too many variable. There really is no need for the liner to be interfacing with the shroud except for the muzzle to avoid clipping. I was shooting my crown Sunday with just one spacer and had no problem getting 3/4 inch groups at 100 yards and a 2 inch group at 200 yards when the wind stayed relatively consistent. 


not saying multiple spacers can’t get that kind of accuracy especially since I have not tried it but having that many spacers simply presents too many variables plus destroying the “free floating” setup IMHO. 


The STX system is different simply because there isn’t any space left in the barrel to have any spacers/orings which I obviously love because I hate those orings!!! I prefer a tensioned setup on impact/maverick because it’s not a free floating design to begin with as the barrel is supported at the end of action/rail. 




 
I recently added two of these to my 500mm Crown barrel. Before adding them, I had one factory spacer on the last 3/4” not covered by the carbon tube, and one poorly bored out factory spacer at the midpoint. I didn’t like that setup, the gun was accurate, but I felt that it wasn’t exactly rigid or secure enough and always left some doubt in my brain. With these new spacers, the interface with the CF tube is much larger and more secure. The o-rings I used, that interface the shroud are very tight, and a bear to get past the threads, but leave no doubt in their fit. Is it better and more accurate? I truly don’t know yet, as the wind hasn’t allowed a real test. It certainly isn’t worse, as I was hitting my 1-1/4” spinners at 97 yards easily and consistently last night. For me, it’s better because it has removed any doubt in my mind about the barrel/shroud integrity, and I was never a fan of the factory spacers.

its could be said confidence gets way better as you feel your gun is set up perfectly im sure it does better with the spacers not to go off keyl lol i put a carbon sleeve i had in my 500mm impact 22 compact and it tightened up my groups at 50 yards as i back to back tested it against the o rings and zero o rings then liner sleeve 
 
Barrel type and gun were not specified. You also stated a carbon sleeve over the barrel which in my mind would mean the shoud as it is part of the barrel assembly. Though, I can see the photo is a sleeve over just the liner. You stated that in the past only the liner was added. Which is true of barrel systems that do not use spacers. Were you using a barrel that did use spacers but removed them entirely prior to the custom ones? Details left out, or conveyed in other ways that aren't really accurate. Not trying to nit pick, just trying to figure out what exactly you have this on first of all, and what you were using prior to this. You asked for comparative results... but what you implied was to a bare liner with no spacers on it at all? All I can picture in my mind is a liner floating in a shroud not correctly aligned and either striking the end cap, moderator, or otherwise flexing wildly when fired. 

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Here is my 500mm superlight Crown barrel. Using factory spacers. Segemented liner epoxied at full length. I chose to use two spacers as I didn't feel quite right about just using one at the end. In my mind, the liner will still flex, and an additional spacer would provide some resistance to this. As well as better allign the liner with the shroud as epoxy set up. These liners, I have no doubt, are not perfectly straight, and if they are, can easily be bent. I know my 380mm liner is bent, but it has no affect on it's accuracy. I havn't got to shoot it much, but at 75 yards it was stacking 21 and 25 gr slugs on top of eachother @ 50fpe.
 
If I could start over I would have epoxied the CF just short enough to put just one factory spacer on the front of the barrel to start the testing there




That’s exactly what I did (epoxy carbon liner sleeve with 1 factory spacer at the end), got lucky with the wind a couple of months back and got my best 5 shot group at 100 yards. 600 mm .22 heavy liner on my crown shooting 27.5 grain NSA at 920FPS. 

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yesterday I was trying to figure out my crown’s consistency problem (mostly sorted I hope) and when my gun was consistent speed wise I had no issues getting sub MOA groups at 100 yards with couple of groups at about 3/4 of an inch. So it’s working for me but YMMV! 
 
There was a thread here about using someone's 'free' print path....

Yes, it's an STL. You can use it with every slicer and so you can print it on FDM or SLA for sure. I have printed the grey left one this morning on a FDM (PLA filament printer).
It's not the same quality as a resinprint, but surely without any doubt usable for the purpose. I have used the same offset and it came out perfect. Just print it slow and use a low layerheight.
This is the link to the STL file of the .25 and .22 spacer.

https://drive.google.com/file/d/1N1wD70NwwPnijqOIOR2yZgzd4_q5upKE/view?usp=sharing
You can print it with FDM or SLA printers. Be sure to use low layerheight as possible in FDM printers. Set printspeed to 50%

I contacted a local printer and it cost me $20 for 3 of these pieces for my Crown MKII 600mm CS Liner.
mike
 
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