Tuner torque spec.?

[gkgeiger]

I’m running a Holeshot tuner on my 2500XS unlimited rifle. I’m using a 7/64 8” long T-handle to tighten the screws. I have been tightening until the tuner won’t turn on the barrel. I’m just wondering if there is a recommended torque spec. so I can be more consistent?

 

[Hi-NV Shooter]

I’m running a Holeshot tuner on my 2500XS unlimited rifle. I’m using a 7/64 8” long T-handle to tighten the screws. I have been tightening until the tuner won’t turn on the barrel. I’m just wondering if there is a recommended torque spec. so I can be more consistent?

Don't know if it is correct or not, but I use 13-inch for any tuner. I think what is important is that you use the same amount of torque each time.

Lee

 

[JerryP]

I use 15 inch pounds.

 

[gkgeiger]

Thanks guys, this gives me some place to start. Didn’t want to over tighten.

 

[ccollier]

I'm also running around 14-15 inch pounds on my tuner. I'm using Fix it Sticks and stop just as it start to touch the short side of 15 inch pounds.

 

[HuskerP7M8]

Torque specs are utterly meaningless unless every barrel's OD and every tuner's ID has the same exact "fit" dimensionally. As a rule of thumb you want about a 0.0005" to 0.001" difference in barrel OD and tuner ID for a press fit.

If that's not accomplished, the torque numbers become increasingly higher as the fit between the two increases. As an exaggerated example, think of what would happen if the 0.0005" fit was increased to say 0.005". It might be possible that you'd twist the head off the screws before the tuner even touches the barrel.

The OP's method of simply tightening the screws up to where the tuner won't move and going no farther is quite literally the only option you have to insure you're not constricting the bore.

I suppose taking a torque reading at that point and using that number every time would save a little time if you're taking the tuner off and on a lot.

Landy

 

[Hi-NV Shooter]

Torque specs are utterly meaningless unless every barrel's OD and every tuner's ID has the same exact "fit" dimensionally. As a rule of thumb you want about a 0.0005" to 0.001" difference in barrel OD and tuner ID for a press fit.

If that's not accomplished, the torque numbers become increasingly higher as the fit between the two increases. As an exaggerated example, think of what would happen if the 0.0005" fit was increased to say 0.005". It might be possible that you'd twist the head off the screws before the tuner even touches the barrel.

The OP's method of simply tightening the screws up to where the tuner won't move and going no farther is quite literally the only option you have to insure you're not constricting the bore.

I suppose taking a torque reading at that point and using that number every time would save a little time if you're taking the tuner off and on a lot.

Landy

You might want to explain that to Dan at KSS. my very first tuner came from them and it was so loose it wobbled, I called and Dawn put Dan on the phone, one question he ask can you tighten it so the tuner doesn't move I said yes and he said that fine then.

Lee

 

[HuskerP7M8]

You might want to explain that to Dan at KSS. my very first tuner came from them and it was so loose it wobbled, I called and Dawn put Dan on the phone, one question he ask can you tighten it so the tuner doesn't move I said yes and he said that fine then.

Lee

Explain what to Dan? What he said is correct and doesn't have anything to do with what I posted.

Maybe you mean you were unhappy with the loose fit, but you have to remember Dan and probably most smiths who bore tuners for a customer know that many customers do a poor job of measuring barrel OD and that forces them to increase whatever fit they like to work with so they don't get complaints a tuner won't slip onto the barrel.

Isn't it much better if the tuner is slightly loose rather than having to return it because it won't slip on and cost time for both smith and customer?

I will say I should have said my numbers of 0.0005 to 0.001" would be what I strive for if I did my own smithing and had both barrel/tuner in hand, but they're most likely too tight of a tolerance for many or most.

I'm curious how loose your tuner was and wondering what your numbers were for the barrel OD and tuner ID in question. I don't really have any numbers for what would be too loose, but I prefer not using a shim because that means additional notes I have to make to insure comparison testing doesn't have another variable that might affect results.

I have approximately 30 custom barrels for use in my test tunnel and maybe 15 or so different tuners that I interchange on many of them often producing loose fits. With thousands of rds of data in my facility testing the concept, loose tuners aren't harmful to precision if you can tighten them down to keep them from moving and the same goes for using shims if torque won't do it.

Landy

 

[striperfisher]

Any gunsmith that tells you to measure your barrel O.D and they will bore you a tuner and send it to you!..Is not fitting a tuner the way it needs to be done...

 

[Hi-NV Shooter]

Explain what to Dan? What he said is correct and doesn't have anything to do with what I posted.

Maybe you mean you were unhappy with the loose fit, but you have to remember Dan and probably most smiths who bore tuners for a customer know that many customers do a poor job of measuring barrel OD and that forces them to increase whatever fit they like to work with so they don't get complaints a tuner won't slip onto the barrel.

Isn't it much better if the tuner is slightly loose rather than having to return it because it won't slip on and cost time for both smith and customer?

I will say I should have said my numbers of 0.0005 to 0.001" would be what I strive for if I did my own smithing and had both barrel/tuner in hand, but they're most likely too tight of a tolerance for many or most.

I'm curious how loose your tuner was and wondering what your numbers were for the barrel OD and tuner ID in question. I don't really have any numbers for what would be too loose, but I prefer not using a shim because that means additional notes I have to make to insure comparison testing doesn't have another variable that might affect results.

I have approximately 30 custom barrels for use in my test tunnel and maybe 15 or so different tuners that I interchange on many of them often producing loose fits. With thousands of rds of data in my facility testing the concept, loose tuners aren't harmful to precision if you can tighten them down to keep them from moving and the same goes for using shims if torque won't do it.

Landy

Ok , Landy thanks for the clarification as I thought you meant any tuner bored more than .001 over what the barrel o.d measured is fitted in correctly.
I just can't imagine how many guys out there would be thinking oh no my tuner is bored wrong.

Lee

 

[Hi-NV Shooter]

Any gunsmith that tells you to measure your barrel O.D and they will bore you a tuner and send it to you!..Is not fitting a tuner the way it needs to be done...

Would this apply to tuner makers as well?

Lee

 

[Link]

So would a screw on threaded tuner be more consistent? Any advantages either way? Why your preference?

ty Don

 

[Hi-NV Shooter]

So would a screw on threaded tuner be more consistent? Any advantages either way? Why your preference?

ty Don

Not for a rim fire which is what we are talking about. and we are talking BR not NRL or PRS those accuracy requirements are different. hitting a steel 12" at 200+ yards is different then trying to hit (.)

Lee

 

[plinker4life]

I’m running a Holeshot tuner on my 2500XS unlimited rifle. I’m using a 7/64 8” long T-handle to tighten the screws. I have been tightening until the tuner won’t turn on the barrel. I’m just wondering if there is a recommended torque spec. so I can be more consistent?

Personally I run 70 in/oz that converts to 4.3in lbs. And its does not move at all, even man handling it. It doesn't take a lot to hold the tuner tight if properly milled. I think you would run into more accuracy problems with it being to tight than too loose. If you dont have a torque driver just go tight enough that its stays in place and no more.

 

[jpx2rk]

FWIW, I just put a JNL tuner on my new RFBR rifle, Joe Chacon just told me to "snug" the screws down so it doesn't move, DON'T overtighten the screws were his words. I did not use a torque wrench as he did not mention one or a torque setting. I'll check the screws for tightness after a few rounds and trips to the range. I don't plan on removing the tuner at all unless something goes wrong, so.....

 

[gkgeiger]

FWIW, I just put a JNL tuner on my new RFBR rifle, Joe Chacon just told me to "snug" the screws down so it doesn't move, DON'T overtighten the screws were his words. I did not use a torque wrench as he did not mention one or a torque setting. I'll check the screws for tightness after a few rounds and trips to the range. I don't plan on removing the tuner at all unless something goes wrong, so.....

You want to reconsider not removing it, mine gets filthy after one session at the range.

 

[Hi-NV Shooter]

You want to reconsider not removing it, mine gets filthy after one session at the range.

it can be cleaned without removing it and more important cleaning the crown.

I use a wood dowel with a piece of fuel line slipped over it and them wrap a 1/2 sheet paper towel rolled onto it some solvent at the the tip and insert into the tuner and twist to clean. works great.

Lee

 

[jpx2rk]

You want to reconsider not removing it, mine gets filthy after one session at the range.

I have a Harrells tuner on my Anschutz, never removed since I put it on about 2 yrs ago, no effect on accuracy noted. I use a tuner tool to clean the tuner and muzzle/crown on the Anschutz, and will try this method on the new set up as well.

 

[gkgeiger]

I have a Harrells tuner on my Anschutz, never removed since I put it on about 2 yrs ago, no effect on accuracy noted. I use a tuner tool to clean the tuner and muzzle/crown on the Anschutz, and will try this method on the new set up as well.

I stand corrected, but will continue to do it my way. Thanks

 

[striperfisher]

Would this apply to tuner makers as well?

Lee

Yep. Why are they any different?