do tuners "cheat" barrel harmonics or is there another way to duplicate previous barrel

[biednick]

Part of the problem is that you're asking for a consistency in ammo that doesn't exist, either. One lot to the next of high precision small bore ammo usually requires a range trip or two to dial in. The physics of how a tuner works is solid.

This is easily solved by just buying a large amount of the same lot of ammo.

The physics makes sense on the surface, but breaks down when you look at what a small weight moved over a small distance actually does. It influences high order harmonics, which are completely hidden by the fundamental frequency and low order harmonics.

By insisting on a huge number of data points you're actually causing the results that you desire. I've no personal experience with tuners myself, but I'm surrounded by data acquisition and analysis every day at work. In R&D work you don't know what you've done unless you can measure it. Sometimes a large sample size works against you because you can't hold all of the other factors in the system to the same value(s) over a long run.

The stochastic nature of a rifle is very well documented. If you can't overcome that (which requires large sample sizes) you can't measure anything either. If the effect of a tuner is so minor its overcome by other variables in a 20 or 30 round group it's not actually helping anything.

 

[P7M13]

I agree with the above comments about barrels from the same steel lot, all chambered and threaded together by the same Smith on the same machine.
Betcha a beer that they'll still have a few quirks between them.

 

[ARlife4me]

I just want to express my admiration for anyone who would buy 5 barrels at one time, knowing he/she is going to shoot through all of them (4000-20000 rounds depending on cartridge and use). You're my new hero!

Now, finding enough of the same primers might be an issue (large rifle) to NOT break the bank

 

[biednick]

It would certainly be nice to see an independent test done on a tuner. Shoot with no tuner, add a tuner and start at zero, and then observe the group sizes at the different settings.

Brian Litz did a very thorough test in his most recent book involving thousands of rounds with a variety of rifles. It's the most clearly presented, rigorous, and concise test I've seen. It was also the first real high profile test and really kicked off the debate. Several other folks on various forums have repeated his testing with similar results.

Then there is the question, "Why did Browning stop manufacture of the BOSS?" This one really hits hard for me.

The big one for me is if tuners work why haven't any of the manufacturers provided any evidence refuting the claims that they only appear to work with small sample sizes? It's certainly costing them sales not to and it'd only take a few hundred rounds to refute the claim if they could.

Cortina changing his tune from "shoot a few groups and you're good to go" to "there's a secret to making them work I can't share because I promised I wouldn't but if you figure it out you'll see they work" is certainly something too.

 

[Brathany]

I just want to express my admiration for anyone who would buy 5 barrels at one time, knowing he/she is going to shoot through all of them (4000-20000 rounds depending on cartridge and use). You're my new hero!

Can an adult adopt another adult? If so, @Mikecr will you adopt me before Christmas?

Bang4theBuck - I know more hunters who aren't shooters, than shooters who aren't hunters! There are guys who shoot a lot every year. The competition guys especially.

 

[Brathany]

Brian Litz did a very thorough test in his most recent book involving thousands of rounds with a variety of rifles. It's the most clearly presented, rigorous, and concise test I've seen. It was also the first real high profile test and really kicked off the debate. Several other folks on various forums have repeated his testing with similar results.


The big one for me is if tuners work why haven't any of the manufacturers provided any evidence refuting the claims that they only appear to work with small sample sizes? It's certainly costing them sales not to and it'd only take a few hundred rounds to refute the claim if they could.

Cortina changing his tune from "shoot a few groups and you're good to go" to "there's a secret to making them work I can't share because I promised I wouldn't but if you figure it out you'll see they work" is certainly something too.

I'll look for the Litz study.
I would trust gas station sushi before a Cortina claim.

 

[BSPPC]

My experience with tuners has shown that they will not make a mediocre barrel great, but they will make a great barrel more consistent.
I tune a new barrel without the tuner, finding the best load. I then put the tuner on and start shooting two shot groups as I move the tuner. I am looking for two things, where bullets dot up and the widest node where the gun stays in tune. I set the tuner where it is accurate and has a wide range staying in tune. Once the tuner is set I do not move it, and if atmospheric issues cause the load to go out of tune, I tweak the load.
I know several shooters that move the tuner to stay in tune, but I don't use that method.

 

[VinceMule]

ARlifeforme, had multiple Hart barrels chambered at the same time with the same reamer in 243 AI, 223, 243 Win, and 22/250 AI. Loads duplicated from barrel to barrel, my hunting partner and I had fantastic success. Back then, we had tremendous p. dog towns to shoot on, and each rifle had a 5 gallon bucket of ammo for the two week trip. The grill guard on my truck had a barrel vise welded on it.

What will throw a monkey wrench into the deal is to change barrel makers or change a twist rate, in which case you start over on your load development.

If you are going to try this, use a top barrel maker that uses a sunen hone machine where the barrels are honed to the .0001 prior to rifling.

 

[WapitiBob]

No idea if tuning is real or not but this was my 600 yard tuning test

5 port self timing brake

1/2 turn out (.021")

 

[RichCoyle]

I am amazed someone would say tuners don't work. I have demonstrated on several occasions they do work. The most striking one was on a guaranteed two minute rifle. Every time I took that rifle to the range it was 2" groups at 100 yards. After the tuner I repeatedly got 2" groups at 300 yards.

Would you also say the rubber donuts don't affect barrels?

 

[coop2564]

I tried tuners and they work...but for me only for that load and conditions of that day. If you have time to retune for days and other conditions good. As a hunter I don't. So it was not any better than tuning a load for my avg hunting conditions and just staying with that. If I target shoot or did competition I would have one for sure. For my hunting they do not help IMO, unless you shoot factory. You can get most factory loads tuned better for a avg hunting conditions, I may tune great or just better. One box may tune under 1" next box might start at 2" and tune to 1.5" but under different weather it will change. Go out of tune some. But that's just what we have to deal with.

 

[Alex Wheeler]

Buy your own reamer. A good proven design from jgs. Stick with the same barrel manufacture and gunsmith. Your tunes will be very close. Pass on the tuner. You can get to the same place without one and you wont be tempted to cheat the real tune. Tuner tuned barrels go out of tune.