The 1 M long CF pipes i got from a aliexperess store.
https://www.aliexpress.com/store/4795009?spm=a2g0o.store_pc_home.pcShopHead_35231473.0 I ordered the flat none coated ones but got the ones that are given a clear coat, the sizes i use as i recall are 14/20 - 20/25 and 25/28 mm.
For my Maverick with a 700 mm barrel i had to cut the pipe into 42.5 cm length, so i had a little to sand the ends on a belt grinder, but left myself too little wiggle room, i should have cut the pipes to 43 cm.
To cut the pipes i used a small cordless angle grinder with a cutting disk, went thru the CF pipes like butter.
These CF pipes are not made to super tight tolerances, unlike the 6 CF pipes Denmark have made for the James Webb telescope. So a direct fit you will not get, so you probably have to do some sanding to get one pipe small enough to fit inside another pipe, in the worst case a pipe might be a little too small in which case you will have to give it some paint / clear coat to make it larger, and then sand the excess away when it have dried.
My money are however on you have to sand, not least with the clear coated pipes.
But it is all work you be able to do in the hand with some 40 grit sand paper, the total FAB time should not exceed 2 hours, at least thats how it was for me.
My inner pipe was a direct fit to the 14 mm barrel pipe on my Maverick, so that was nice, but i was prepared that i might had to do something there too.
Pipe #1 i just had to sand a little on the clear coat to get it to fit inside pipe #2, pipe #2 in turn i had to go to town on to get it to fit inside the outer pipe #3, so here is where i had to sand in the CF itself, and that do get messy so be aware of that and the problem of breathing in CF fibers,,,, i personally used a disposable corona face diaper and had my back to the wind.
There still is the matter of the very inner CF barrel sleeve from FX, while it fit as i would like / expect on the Superior barrel it fit poor in the barrel pipe, we are talking several 1/10 of a mm here, so i will have to paint that pipe to make it larger, and then sand it down for that perfect fit.
But i am not going to do that before i get a 700 mm long .177 slug liner, ATM there are a little tape on the inner CF liner to make it fit sort of OK in the barrel pipe.
Regarding the stiffness, then yes i think it is there, i turn 56 this year and it have been many years since i had anything that stiff in my hand
As this is a 3 pipe deal, you could probably just cut some spacer disks of the middle pipe to act like spacers like the O rings do on the stock rifle, but i dont carry my Maverick around much and what ever extra weight the full middle CF pipe make make no difference to me. And this way if some Zombies try and rush me while out shooting i can use the Maverick as a bat though i will probably end up with just the barrel left in the hand as lets face it the FX rifles are not bulldozers.
