Show me your barrel "harmonic" tuners

[bigHUN]

I have this FX shroud integrated tuner for my x700 barrel, I was using it with more less success in the past 2-3 years.
Tinkering now for a new season to swap the barrel on my Impact MK2 from .25x700 to .22x600, and maybe I would need to build one tuner for that shorter barrel.
I know what parts inside the integrated shroud, I may want to go now with an independent piece that just slides along the outer tube.
Show my how you managed?

 

[SpiralGroove]

30MM SINGLE Split 1-PC Clamp Shaft Collar Steel, Black Oxide NEW 1 PK | eBay

SCREW M6X18.

www.ebay.com

Somewhat crude, but works fine .... not as precisely ...... incremental. Once the spot is found - your done.

My outside moderator tube is 30mm, but if yours is a more standard size .... they're significantly cheaper.

 

[one1bird]

There’s pretty then there’s pretty quiet

 

[Motorhead]

This just a couple random pictures, but I do this type design on quite a few of my High output PCP's.
Barrel gets held at receiver VERY securely. Threads on or added at barrels muzzle end.
Ideally thin wall SS or CF shroud.
Air stripper end cap when threaded on and snugged up places compression on shroud tube & barrel within shroud into STRETCH tension.

This design works exceptionally well IMO

 

[Centercut]

Yes. Some seem to be tensioned against a fitting that is tight on the barrel and not against the breech, like the new tensioner for the Ghost. This one also has the new barrel clamp. Belongs to @5Power

 

[mubhaur]

This just a couple random pictures, but I do this type design on quite a few of my High output PCP's.
Barrel gets held at receiver VERY securely. Threads on or added at barrels muzzle end.
Ideally thin wall SS or CF shroud.
Air stripper end cap when threaded on and snugged up places compression on shroud tube & barrel within shroud into STRETCH tension.

This design works exceptionally well IMO

View attachment 443998

View attachment 443999

Great further detailed pics would be even more helpful.

 

[Motorhead]

Great further detailed pics would be even more helpful.

Each application will differ .... How one secures barrel within receiver to how one makes sure all the pieces are mechanically SQUARE to each other is key !!
If you require / want impulse air INTO the shroud ? your muzzle end tensioning cap needs to be vented.
Sadly no pictures at this time ... never documented this mod tho having done so numerous times.

 

[OldSpook]

Here is an approach I took with a spring rifle.

Tuning - Tuning Tanto Install on an HW98

I've been shooting this HW98 for several months now. It is a fine rifle. The trigger is excellent for a bone stock Rekord. It is a two stage with a clean pull to a second stage which creeps a tiny bit but breaks around 20 ounces. All in all quite manageable. The rifle has a "muzzle...

www.airgunnation.com

 

[bucketboy]

This just a couple random pictures, but I do this type design on quite a few of my High output PCP's.
Barrel gets held at receiver VERY securely. Threads on or added at barrels muzzle end.
Ideally thin wall SS or CF shroud.
Air stripper end cap when threaded on and snugged up places compression on shroud tube & barrel within shroud into STRETCH tension.

This design works exceptionally well IMO

View attachment 443998

View attachment 443999

I assume this is an fx liner that you have sleeved for a different gun? If so, how did you securely fix the 1/2 unf thread to muzzle without it being pulled off hen tensioned and how did you stop air escaping pasted the rifling groove inside the sleeve?

Bb

 

[bucketboy]

Question, do barrel tuners have any use on lower power guns

Bb

 

[Motorhead]

I assume this is an fx liner that you have sleeved for a different gun? If so, how did you securely fix the 1/2 unf thread to muzzle without it being pulled off hen tensioned and how did you stop air escaping pasted the rifling groove inside the sleeve?

Bb

A simple touch up of the barrels O.D. uniformity for the distance the threaded over sleeve would require. Barrel O.D. at muzzle and I.D. of threaded sleeve at a basic zero / zero fit. Loc-tite 680 when assembled and nothing moves under tension.

In the case of FX liners the above

 

[Nattboy]

A simple touch up of the barrels O.D. uniformity for the distance the threaded over sleeve would require. Barrel O.D. at muzzle and I.D. of threaded sleeve at a basic zero / zero fit. Loc-tite 680 when assembled and nothing moves under tension.

View attachment 445497
In the case of FX liners the above

I hope your shoulder is on the mend.

 

[bucketboy]

A simple touch up of the barrels O.D. uniformity for the distance the threaded over sleeve would require. Barrel O.D. at muzzle and I.D. of threaded sleeve at a basic zero / zero fit. Loc-tite 680 when assembled and nothing moves under tension.

View attachment 445497
In the case of FX liners the above

Thanks I sleeved a liner to fit into a Rapid, I did it the same way as you including the loctite but I didn’t do the tensioning for a couple of reasons

Firstly I wasn’t convinced that the loctite would hold it securely enough when put under tension (obviously it does)
Secondly I was concerned that the torque on the liner while tensioning it would cause it to twist inside the sleeve causing more problems than it was trying to resolve. I did come up with a solution where I could hold the 1/2 thread so that it didn’t rotate when installing the moderator but in the end, I couldn’t be bothered

Bb

 

[Motorhead]

I hope your shoulder is on the mend.

It is getting better by the week .. thanx for asking

 

[bucketboy]

Yes. Some seem to be tensioned against a fitting that is tight on the barrel and not against the breech, like the new tensioner for the Ghost. This one also has the new barrel clamp. Belongs to @5Power
View attachment 444002

I keep looking at this and while I I understand they might work well on a thinner barrel or if the tensioning shroud is a large Dia, I can’t help but wonder, do they really make that much of a difference on say a 16mm barrel with a 20mm Tube? Surely the flex point is where the barrel is held in the block, not the barrel itself.?

I don’t have any experience of target shooting large calibre at high power but I get the reasoning with regards to harmonic tuning but wouldn’t a barrel tuner be more predictable than tensioning the barrel then screwing on a moderator.

One more question, am I right in assuming that the tensioning shroud is to aid stiffness but then if a barrel were then to be accidentally knocked in some way, wouldn’t it take longer for all the parts to fall back into equilibrium?

What are the real world experiences using tensioning systems

Thanks

Bb

 

[bigHUN]

I tried the barrel tensioning system on a x700 liner, but realized I like the harmonic tuner shroud results more. At the time of my testing the two scenarios were not interoperable.

 

[Centercut]

I keep looking at this and while I I understand they might work well on a thinner barrel or if the tensioning shroud is a large Dia, I can’t help but wonder, do they really make that much of a difference on say a 16mm barrel with a 20mm Tube? Surely the flex point is where the barrel is held in the block, not the barrel itself.?

I don’t have any experience of target shooting large calibre at high power but I get the reasoning with regards to harmonic tuning but wouldn’t a barrel tuner be more predictable than tensioning the barrel then screwing on a moderator.

One more question, am I right in assuming that the tensioning shroud is to aid stiffness but then if a barrel were then to be accidentally knocked in some way, wouldn’t it take longer for all the parts to fall back into equilibrium?

What are the real world experiences using tensioning systems

Thanks

Bb

For real barrels that are solid and reasonably stiff, I think that barrel clamp is effective. IMHO the “tensioner” is more psychological than anything else.

 

[bucketboy]

For real barrels that are solid and reasonably stiff, I think that barrel clamp is effective. IMHO the “tensioner” is more psychological than anything else.

Ah, ha, that’s the conclusion I have came to

I have never tried a barrel weight because at the power levels I shoot at I haven’t noticed any accuracy issues that can’t be solved with a different size, weight or brand of pellet but I can definitely see that longer barrels with higher power may well benefit from some form of harmonic damping, a simple weighted bush that can slide along the barrel would be my first choice


Bb

 

[mubhaur]

I have recently done some experiments on FX Impact. Even after installing the thicker upper plate and a solid barrel, there was a bit of POI shift.

Finally removed both O Rings from the cocking block etc. Turned down the dia of barrel by 1/2 mm at those areas where the barrel could touch any other part of Impact than what I wanted.

So now my Impact's solid barrel is touching only inside the breach block and the barrel holder. The rest of the barrel is free floating, at least not affected by any other known variables.

The POI is not shifting at all, day after day and session after session. So far it is holding POI as good as RAW holds.

Bhaur

 

[bigHUN]

I wanted one of those upper backbone plates, but for different purpose. I even designed it and was ready to source to a friends CNC shop. And I changed my mind, I made a one piece rest instead.
My initial idea was to move the picatinny length backward towards the shooter for about 150-180 mm, but then I transferred that feature to the rest. I wanted to sit behind the gun stock and look through the scope instead of resting my cheek on the gun.