Tuner questions

[BradY]

Hopefully Erik or Steve or someone who shoots f class with a tuner will be able to answer this for me.

Im going out to do my load development on my 284 shehane tonight with a barrel tuner fitted. I plan to start the tuner on "0" which is flush with the muzzle. It weighs in the vicinity of 700grams that must be close to 1 pound and is on a 30 inch 1.25" straight profile barrel. I went heavy as I have weight I can make up in the rifles overall weight.

Now my questions are:

How far (length) does a tuner take in distance adjusted forward before it changes group size. To explain it better. Say my tuner on "0" is flush with the muzzle. As it screws out, it moves beyond the muzzle further forward. 24TPI to me means one full revolution should be just over 41 thousandths. Now could I move it 2 thou and expect group size to change, then change again at 4, 6, 8? Or is it more or less than that each time?

And also, if you find a good tune point say at 8 marks past your zero mark (that would be about 21 thousandths on my tuner) are you better to stay there or would the tuner be more effective again winding it one or two full revolutions past that point and starting again? To me the tuner would be more effective the further the weight went past the muzzle but there is alot of distance in tuner travel that can be tested. I guess Im asking am I better starting further out or closer in?

Thanks

 

[Erik Cortina]

With my tuner I test every .003" first to cover the range. .001" will make a difference, so don't move more than .003" at a time.
If you find a good tune, there is no need to go further out, as all you will do is find the same node again, much like when we adjust seating depth.

I like to start closer in and work my way out due to the nature of my tuner. The closer in it is, the less gap there is between tuner and barrel, so the tuner is less noticeable there.

 

[BradY]

Thanks very much mate, I did my powder charge testing this afternoon with the tuner all the way in. Mine sleeves over the barrel so there isnt any areas to notice by it screwing out. I must put a pic up soon you will probably cringe at how big and ugly it is ;D

Results at 100yds are quite positive, although the barrel was cleaned to steel last time and even though I fired two foulers off the target first, the first shot of each charge was a long way out of the group before it settled. However the following two shots of each were good I feel, to the point two charges produced identical groups, even with the first shots being outside the group. And the charge after those two had the final two shots in the same hole with the vertical location the same as the previous two. Shows me a 0.6gr node there. Will work on the middle charge and do the seating depth before moving that tuner. Its the best results Ive seen on this barrel so far.

Thanks again!

 

[Alexander-M]

BY1983,

Just in case the overall weight of your rifle is significant to you - the tuner weight at 700 grams is actually 1.54 pounds. Glad it is working out for you.

Nando

 

[BradY]

Yes our maximum weight in FO is 10kg. The rifle prior to the tuner was just over 9kg so this extra weight is fine.

 

[Jay Christopherson]

BY1983,

Just in case the overall weight of your rifle is significant to you - the tuner weight at 700 grams is actually 1.54 pounds. Glad it is working out for you.

Nando

Holy moley, I have to see a tuner that weighs 700 grams! @BY1983, can you post some pics? I'm seriously really curious to see it and to hear how it works out.

 

[Erik Cortina]

Here is a picture of BY1983 lifting his barrel with two tuners installed. ;D

 

[ShootDots]

Here is a picture of BY1983 lifting his barrel with two tuners installed. ;D

It appears like the barrel is bent! Are tuners THAT heavy! I am too old to use one>>> I would not get my rifle to my car from the house!! LOL!!!

OH! I get it now, it is in the unlimited class!!!

 

[BradY]

Erik, its not that far off!

Here is a crappy iphone pic. 48mm diameter by approx 75mm long from memory. I can take some better pics tonight when I get home.

 

[BradY]

As far as working out, well I shot against Marty Lobert recently who came second at the FCWC individuals. His tuner is huge but not sure if its adjustable, or just installed as a fixed weight dampener. Man that gun shoots. I figure that the amount of weight does no harm- as my powder charge testing seems to have shown, and yes I have that extra weight available to be used up out of my 10kg limit, but cosmetically its not the prettiest thing you have seen.

Time will tell I guess.