At least one tuner limitation

TomD

TomD

e publius unum
I've had an unused tuner sitting in the parts bin for a few years but had done nothing with it. Last year I got a rarity, a 30 BR barrel that just wouldn't shoot, period. I played with it for a couple of months and dropped a disastrous 2 points on a Postal match on a totally calm day for our team's only dropped points for the year. At that stage, I reinstalled the previous barrel.

Seemed to be a pretty good experiment to put the tuner on the take off barrel to see if there was a miracle in the works.

Today, I fired around 25 3 round "groups". I started with the tuner as far out as I could and worked inboard in increments. I can cut to the chase here as say that not one of the 25 "groups" don't have at least one distinct single bullet hole. By moving the tuner, I could make the group point of impact move here and there around the target; sometimes a very small adjustment could move it dramatically. Some adjustments would make the "group" pure vertical and others, horizontal. I did shoot multiples of some adjustment points and the shape did remain the same. What I could not do was make this rig shoot less than the mid-.3's for 3 shot groups. Horrible.

The load is one that has shot very well for me over a couple of barrels: a 118 gr 10 ogive bullet seated at jam, 63.5 clicks of VV130, Fed 205, fresh brass. I didn't change the load and tried to tune exclusively by tuner.

Tuners may work but they won't turn a trash barrel to gold.

tuner.jpg
 
Last edited:
Tom,
In my very first session with Tony B. at one of the schools at Rachel's Glen I had a new barrel from one of the bigger barrel makers. It would shoot 4 shots into a small group but there would always be a flier. Not always the same shot but it would throw 1 out of five every time. Tony and I worked with it all day and it never failed. Tony called it a 'puker' because he said it would puke a shot and would always do it. He said such a barrel would tease you by making you think "If it will put four in a hole it will put five in there." Not so. I pulled the barrel with 160 rounds on it and gave it away.

I told the new owner what it was doing and he later told me that it did it with him. Every group. Don't have a clue why but I know that it will.
 
TomD

I would be interested in having that "no shootin" 30BR barrel...What action is it threaded for?...What is the overall length?..What is the twist?
Send me a PM and let's make a deal...:rolleyes:
 
Tom, since you have gone to all this trouble, why not utilise the thread on the muzzle and get yourself a piece of alloy tubing and stretch the barrel. It would be interesting to see if there was any change in the performance.
Years ago i had a 7mm barrel that would orbit just one shot out of the five and was a real nuisance when shooting long range matches. By stretching it it was cured of the stray and served me very well for its life after that.
It is worth a try.

Tony Z.
 
Sorry Boyd,


On my comp the pic came in so big that some of the info was cut off..........thought you missed it. :)


al
 
I'd like to know....

...if you can check the bore for straightness; and, if noticibly crooked, mark it and see which way it is pointing when mounted.

Jim
 
Boyd Allen said:
Tom,
How did it group without the tuner?
Click to expand...

It shot what I call caterpillar groups, lines going off one one direction or another plus the occasional flyer. :D I didn't exactly try it at any group matches and the groups were bad enough that I was never motivated to do much measuring but I would guess in the high-.3's and up.
 
Last edited:
I guess my point is that you may have gotten some improvement, but not enough to salvage the barrel for its intended purpose.
 
Tom

At this point, I agree totally with you. A tuner will not make a bummer into a hummer. I do believe the following though:

1. The extra mass of a tuner, solidly mounted, will slightly improve a barrels accuracy by dampening the barrel's vibration a bit.

2. A tuner gives you a different way to tune as conditions change.

3. The heavier a tuner is and the further forward the weights are mounted, the wider a tune window will be. I have yet to add enough weight, to a muzzle, to determine if Calfee's "stop" will actually work on a short range gun.

These days, a Saturday at Denton will see about a dozen tuners being shot on bench guns. Each shooter seems to be well satisfied with the tuner's ability to tune for DA changes. I watched Jon Conley set up his bench with his tuner equipped 6ppc bench gun. He took a DA reading and then changed the weight position the required amount of numbers to match the DA. He then sat down and shot a four shot dot with one bullet out enough to make the group a big .1XX" group, on the first group of the day. After a bit of well deserved bragging he put the gun back up and hung out for awhile before packing up and going home.

You can do the same thing by charting your gun's powder weight preference as compared to DA. But, with the tuner, I think you can load at home and tune with the tuner at the range. This'll be an interesting year at Denton. At this point, about half of the bench guns (at least the PPCs and a few 30s) will be equiped with tuners. The non-tuner crowd and the tuner crowd both have some very good shooters. We should be able to really determine if the tuners work as we believe at this time. I'll be the first to admit that practice results don't equate to won matches.

Saturday, we had windy conditions that offered a straight 10mph cross wind and almost no head or tail winds. Not my favorite conditions, but I wanted to try out my flavor of the week. I had re-chambered a proven "good shooting 30" from a straight 30BR to a 30BRX1/4 which is a 30 with a .125" long chamber. Using an extra set of weights I loaded enough Benchmark to get 2980fps and shot a group which gave a shotgun pattern. I turned one set of the tuner weights out 1/2 turn. The group had all bullets touching in a vertical worm. I turned the weights another 1/4 turn out and shot a group that had very little vertical. Another 1/8 turn out and I shot a .190" group (measured with a Hart measuring device) that had a small amount of horizontal due to wind.

I still have the magnet on the tuner and I've adjusted the stock mounted magnet to it's lowest position so as to, hopefully, just offset the barrel's sag due to it's and the tuner's weight. Jerry Hensler suggested that I mount a couple of magnets above the barrel to lift only the sag from the barrel but I'm too lazy and busy at this time to build the required mounting bracket. So, I'm still using the opposing force magnets to try to do the same thing. The gun, with a ,really good, proven barrel shoots well. I have no idea how to spread the blame between two sets of weights and a set of magnets and a good barrel. I can say that the conglomeration of stuff out on that muzzle shoots well indeed.

PS All opinions subject to change as we shoot these things, in competition, enough to tell what benefits the tuners really offer.

The gun weighs just less than 11 pounds with all of this stuff on it and a 21" heavy varmint contour Shilen. I think I can make LV weight with a different action and with only one set of weights.

IMG_2035.jpg
 
Last edited:
Tuners

I have been saying for the past three years that a tuner will only allow a barrel to shoot up to the same potential as with the standard tuning techniques, no more.
The advantage of the tuner is you have the option to vary the tune in an instant at the line. Once you learn this, and are willing to do it, you will see that it is a worthwhile addition.
Yesterday, at Tomball, a bunch of us were out having a good time getting our stuff in line. I set back two barrels that go on my Sporter, I had finished up last season with them on a good note.
With my pet load, I was locked into about a bullet hole of verticle. My usual proccess of going a half turn and checking it didn't seem to be working, so I just cranked the thing around about 1 1/2 turns, which amounted to about .040 advance. I shot a couple of three shot groups that looked real good, and then two five shot groups that were about .100, and about .150.
What I probably did was just pass up the node, and sort of stumbled onto the next node when I turned it that much.
Anyway, I feel confident that the barrel is ready to go to the line.
Gene Bukys, Vic Smith, and I were talking about this late yesterday, and I still haven't quite found out where one node ends, and the next begins. Mainly, because when I hit the setting, I just leave it there untill the Rifle looks up and says, "I feel ragged". I suspect with my tuner, at 5.5 ounces on a 36 tpi advance, it is about 3/4 turn, or about .020 inch.........jackie
 
Yep

The barrel is threaded for one inch at 32tpi and the weights are threaded at 32tpi. This tuner locks up to the muzzle just like a muzzle brake does. Although it's hard to see, in the photo, there's about .010" clearance at the aft part of the tuner. I feel that a good solid lock up is important to force the tuner to vibrate with the barrel instead of having a pattern of it's own.

It was a pain in the butt to get that stinking magnet clocked around till it opposed the stock mounted magnet. It took several trips in and out of the lathe to trim the muzzle till it lined up properly.

Shelley
 
Last edited:
You must log in or register to reply here.
Back
Top