FX Impact barrel torque

[Paio]

Does anybody know what would be the ideal torque for a 600mm barrel nut on a FX Impact STX .25? 

And, anybody could suggest/recommend a a suitable torque wrench for that? 

I have read about it months ago and how it affects accuracy. It would be nice to repeat the same torque when reinstalling the liner. 

 

[2fast2furious]

Steve and that airgun gear guy from Europe did a review on changing liners. They said just tighten it till its snug. Dont over tight. It ain't like changing a tire on a car that you need a special curtain torque for each model or its gonna fall out. I tighten mine till I feel its tight enough but not too tight I would damage it. Dont have a problem with the nut coming loose.

 

[heavy-impact]

You just want to hold it in place. As a rule of thumb compression will allow a rigid object to vibrate like a bass string.

 

[bucketboy]

You just want to hold it in place. As a rule of thumb compression will allow a rigid object to vibrate like a bass string.

This is exactly why as soon as I get my impact I am making a quick change system that hold the barrel neither in compression or tension, much like a collet on a lathe or milling machine. It will also allow me to fit any length liner without the expense of the new barrel sleeve.



Bb

 

[bubblerboy64]

Vibration. You know that’s perhaps something that might be pretty relative to these sleeved barreled guns . When I removed the barrel nut the liner definitely has some directional torque on it. It might just be a benefit to reduce that and certainly reducing vibration should be a positive 

 

[Ellcrow]

Any news about ideal torque for a 600mm barrel nut on a FX Impact STX .25?

 

[tor47]

Roughly a quarter turn: https://fxairguns.com/wp-content/uploads/2019/06/liner-replacement-eng.pdf

 

[Bob_O]

I always do hand (finger) tight then 1/16 turn with a wrench. If you truly got it hand tight, then it should snug up nicely by 1/16 turn. If not, then only enough after that until you feel it snug up.

I've never had a problem with accuracy.

 

[Airgun-hobbyist]

I wrapped the end of my barrel liner with Teflon pipe thread tape where it slides into the barrel nut. This takes up the little bit of slop between the barrel and nut for a repeatable snug fit. Then just barely snug the nut to tension it. As Bob_O says, a 1/16 turn from finger tight should do it.

 

[bigHUN]

Finger tight only with the allenkey, two fingers, do not hand torque as with your grip.

1-2 Nm max, 3 is already too much, 5 Nm torque is for bicycle seat post btw.

If you really want numbers I have precision micro adjustable torque wrenches and next time I have it in my hands I can measure. But you don't want to buy those tools, $$$$

 

[Bob_O]

It takes an open end or crescent wrench.

 

[carlos_hathcock]

I have found best results screwing it in until it just touches the muzzle and no more. Light index finger and thumb just until it stops and no extra torque. I found worse accuracy putting any torque on it.

 

[Airgunmann]

I made a spacer for mine out of a carbon fiber sleeve measured down to the cf liner and into the nut and found there was about a 3/8 of inch gap between the two so that's about what I put in it so it wouldn't compress the barrel

 

[MongooseV8]

If you wanted to use a torque wrench you can use a crows foot on the end of a traditional torque wrench.