Fx 700mm barrel tensioner kit- solution for increase in muzzle crack

[Redwolfpaul25]

Hi everybody.

Recently i installed a installed a 700mm fx tension kit onto my .25 M3, not so much to see if i can increase accuracy as its already quite good but moreover to see if i can eliminate POI shift ( jury is still out on that one !).
Obviously removing the fx factory shroud and replacing it with the carbon fibre shroud and jam nut has ment that there is quite a increase in muzzle report as my current tune is pushing 41g slugs at 960fps ( some 80 odd ftlbs) and my 0DB sound mod is not coping very well. Has anyone else experienced this ? Im thinking of putting a carbon fibre tube cut to the appropriate and sliding that over the barrel tension tube to see if that soaks up any of the sound, next will be seeing about a different sound moderator, maybe a donny fl Ronin or something else.

 

[Ca_Varminter]

When I happen to learn about this tension barrel system, got my engineering juice flowing....
So I just happen to go the way of Ernest Rowe!! By using the existing shroud or Harmonic tuning shroud.
I installed a second barrel securing screw on the opposite side on rear block.

This is to insure the barrel is solidly secured in the rear block.

Then I ordered a piece of 20mm od x 14mm in Carbon fiber tube. And cut the needed length on my lathe...
This is placed between the rear of the shroud and the front barrel support.

I also dimple the steel extension between the barrel tube and brass transfer port thimble.
For the barrel securing screw x2 to secure to...
So as I tighten the shroud, tensioning most of the barrel (from the rear block forward),
The barrel would Not slip forward!!

Now I grab the shroud and tighten down..
The next piece I will fabricate is a hex extension that will be threaded to fit the 1/2-20 moderator extension.
This so I can use a Torque wrench to establish a reference point to how tight I am tensioning the barrel system!!

So I go from no add-on moderation(bit of a crack) to Fatboy with extension and baffles for stealth

I will be needing to cut another piece of CF tube when I get my 800mm barrel!!

Stuart

 

[Centercut]

Try an STO Falx High Flow moderator. I have the same setup .25 Impact 41 gr ZAN at 950 fps and it’s not too loud.

 

[qball]

FX shroud strips approximately 30% of the air so that 30% air and energy is now hitting the moderator without a shroud. Only way to address is higher volume(at least 30% larger) moderator AND different baffle design to cope with the additional blast of air.

STO @Centercut has mentioned seems to work well along with shogun from DonnyFL. Not only you need more volume you need more distance/length to diffuse the additional energy . With that much energy I only shoot at the range so I just use my FX moderator since I have double ear protection at the range anyways, maybe you are lucky enough to shoot that at home.

 

[Redwolfpaul25]

A very helpful chap gave me the solution to this increase in muzzle crack.
1. Remove the rear conical part of the factory shroud off, using a hot air gun to release the glue.
2 . Using a marker pen or some masking tape, mark the point on the barrel tensioning carbon fibre where the factory shroud ends ( you will need to screw the factory shroud on to see where this is.).
3. Using a length of amalgamating tape or similar, form a oring of the correct diameter on the carbon fibre shroud and then install the factory shroud back on. It should be a tight fit as to ensure all the air goes back up the shroud and out of the sound moderator.

You can use rubber strips to form the oring/ air tight seal as this will work well to, just ensure its a tight seal, i used a spray of ballistol stock cleaner to help lube it on.

It is my intention to get the rear conical part of the shroud and get a engineering friend of mine to turn down the conical part to the correct diameter so it can slide over the barrel tensioner tube.

 

[Smok3y]

I would probably suggest an STO as well. I just picked up a Falx in moderate flow for my setup (completely different), and I was surprised at the difference. My STO a few years ago was good, but I didn’t see a big difference between others. This Falx has been a surprising difference compared to others. I only got to try it why tuning, and haven’t shot any groups yet, but reports here are that they are great accuracy wise. Lighter weight than others too. And the Falx is a great price compared to most out there.

Because he changes internals to adapt for different flows, it seems like his model above the Falx or the Falx in high flow could be great candidates for you.

 

[6gun]

Hi everybody.

Recently i installed a installed a 700mm fx tension kit onto my .25 M3, not so much to see if i can increase accuracy as its already quite good but moreover to see if i can eliminate POI shift ( jury is still out on that one !).
Obviously removing the fx factory shroud and replacing it with the carbon fibre shroud and jam nut has ment that there is quite a increase in muzzle report as my current tune is pushing 41g slugs at 960fps ( some 80 odd ftlbs) and my 0DB sound mod is not coping very well. Has anyone else experienced this ? Im thinking of putting a carbon fibre tube cut to the appropriate and sliding that over the barrel tension tube to see if that soaks up any of the sound, next will be seeing about a different sound moderator, maybe a donny fl Ronin or something else.

We lost the air stripper and first moderator when we ditched the shroud. I use a ronin on my 22 at 70 lb/ft. Its not secret squirrel silent anymore but its not loud enough to get my neighbors out to investigate the sound.

 

[6gun]

I came up with a solution for my setup. I have a shrouded tensioner now. Fully functioning air stripper and shroud helps supress it along with a ronin. 3/4 pipe is not the correct thread but i turned a plumbing fitting on my manual mill since i dont have a lathe and doctored it up to work, and put an oring groove in it. My 700mm 70 lb/ft 22 is back to dead sneaky.

 

[6gun]

 

[6gun]

After the brass proof of concept, i cut up my factory shroud rear cap since i have a carbon tuner shroud in inventory. Eventually it was done right.

 

[6gun]

It fixed the muzzle report issue and fits much better. If you dont have access to the tools that i do(just a mill for me) , a machine shop could easily and cheaply modify your existing shroud tail cap. You will need to get a proper oring(i used a spare from my burnt up cx3 compressor) and have the cap bored(mine is 20.3mm i-d) , cut and have an oring journal machined in. The work took me 1 hour as a hobbyist on a milling machine larping as a vertical lathe

.

 

[Redwolfpaul25]

This is excellent @6gun ! I really like how you have done this. So far my method of using almalgamating tape has worked but i think i will definatly use your method now.

 

[Ca_Varminter]

When I got my 800mm barrel setup I decided to do a little change to how I secure the barrel.
Rather I than dimpling the barrel housing extension... I decide to cut a groove!
The make sure any displaced metal from cranking on the grub screw will not hinder the removal of the barrel from the rear block.
Also it makes sure I get a Positive No Slip Securing of the Barrel...

 

[6gun]

When I got my 800mm barrel setup I decided to do a little change to how I secure the barrel.
Rather I than dimpling the barrel housing extension... I decide to cut a groove!
The make sure any displaced metal from cranking on the grub screw will not hinder the removal of the barrel from the rear block.
Also it makes sure I get a Positive No Slip Securing of the Barrel...

Sound logic! I might mill a flat in mine like a limited version of what you did since i dont have a lathe.

 

[6gun]

I recently modified my carbon harmonic tuner shroud to fit over the tensioner. The level of extreme control it offers and noise moderation it offers in conjunction with a ronin at 70 ft/lbs (22)is excellent! Pick a power level/performance envelope, dial the group in with the tuner and keep the super secret squirrel noise levels! I hope fx offers a modular threaded tail cap on shrouds for people without machine shop tools one day. We know how they love to market acessories that interact with each other.

 

[BHainz]

I've been looking all over for a solution like this. I ordered a couple extra of the shroud tail caps from FX and am planning to modify them to fit over the carbon fiber tensioning system.

 

[6gun]

I've been looking all over for a solution like this. I ordered a couple extra of the shroud tail caps from FX and am planning to modify them to fit over the carbon fiber tensioning system.

The hardest part is the oring journal to seal the shroud air pulse. Other than that its really easy. I dont recall the oring size, i just grabbed one of the spares i had for one of the many pcp compressors ive worn out where the rebuild kit they provide was pointless. Empire of dirt mods

 

[6gun]

I should add, the harmonic tuner (at least my carbon shroud version) still has a effect with a tensioned barrel which is nice. Ive turned my impact into a boat anchor liner>carbon stiffner>barrel tube >carbon tensioner>carbon harmonic tuning shroud >ronin. It lets me find a nice middle ground for shooting monster redesigns close in, 23 javelins at 1050 out to 150 yards and 31 nsa's and just under 1k fps to 250 yards with good precision and only using the power wheel and its still super sneaky quiet which was a MUST for me.

 

[amindz05]

After the brass proof of concept, i cut up my factory shroud rear cap since i have a carbon tuner shroud in inventory. Eventually it was done right. View attachment 294547

hello after all the modification of the cap is that I tighten the cf tube with tensioner nut or with the shroud? thnk u

 

[6gun]

The shroud floats as intended, tension the bbl with the cf tensioner as desined, screw on the shroud and proceed as usual. I just bored out the back to alide over a cf tensioner instead of the blued barrel tube.