Anybody put a BOSS on a custom barrel?

[dwinmeade]

Are 2-shot test groups as statistically significant as 10-shot ones? That is, the same size?

2 shot groups are to find the rifle's various "nodes". If you shoot more than 2 shots, then which distance from which shots represents the true "node" spread?

Once you get the best group at that particular "node", adjust your POI to your liking. Theoretically, all future shots should land between the 2 original "node" shots.

However, we both know the human factor enters in, spoiling things. AND...as the barrel heats up, shots will wander outside the "node" group size.

The people at RAS Tuner say you can move the Tuner as the barrel heats up and keep the group size. I haven't tried that as of yet, as it would take some trial and error to figure which direction and how much.

As to your 2 group vs 10 group significance...the 2 shot group is the building block and the 10 shot group is the confirmation...THAT...the RAS Tuner did it's job.

 

[Rich Coyle]

Are 2-shot test groups as statistically significant as 10-shot ones? That is, the same size?

When I first installed the adjustable brake the 'smith told me, "If it doesn't shoot two close together it won't shoot three any better." Don't waist ammo why testing a tuner.

 

[Bart B]

2 shot groups are to find the rifle's various "nodes". If you shoot more than 2 shots, then which distance from which shots represents the true "node" spread?

The extreme spread of the widest two shots. Shoot some 10 shot groups carefully noting where the last 8 are relative to those first 2 shots.

This is the first time I've been made aware of this theory or reasoning. The odds of the first two shots being the extreme spread of several or many shots is about the same as getting box cars on the first throw of a pair of dice in a crapshoot.

Once you get the best group at that particular "node", adjust your POI to your liking. Theoretically, all future shots should land between the 2 original "node" shots.

Of the thousands of 5 to 10 shot groups I've fired with a given sight setting, less than 1% were smaller than the extreme spread of the first two.

AND...as the barrel heats up, shots will wander outside the "node" group size.

I've shot 20 to 30 shots 15 to 20 seconds apart and none wandered away. So have hundreds of others shooting 40 to 50, Our barrels were fit to receivers whose face was squared up with the barrel tenon thread axis. No single hard touching point whose expansion from heat buildup caused point causing more barrel whip in that direction upon bullet exit.

This link is full of misleading and incorrect information:

RAS Tuners - RAS Tuning Instructions

RAS Muzzle Brake Tuning System - Accuracy with RAS: The tuner experts. RAS manufactures and distributes the highest quality rifle tuners and tuner-brakes for competition shooting.

www.bostromgunsmithing.com

 

[Rich Coyle]

Bart B,

No matter how many times you post what you posted it will not change the fact if your rifle doesn't put two close to each other regularly it will not put three close regularly. By adjusting the brake on my two MOA rifle I brought it down to 1" at 300 yards by firing two. If they weren't close I adjusted and fired two more until the two were touching.

 

[dwinmeade]

Bart B,

No matter how many times you post what you posted it will not change the fact if your rifle doesn't put two close to each other regularly it will not put three close regularly. By adjusting the brake on my two MOA rifle I brought it down to 1" at 300 yards by firing two. If they weren't close I adjusted and fired two more until the two were touching.

Rich, I believe that some that reload don't understand (thus 'misunderstand') tuners. Tuners are in direct opposite of reloading...

Reloading is where you try to match a reload to the barrel's best harmonic "node" (not using factory rounds).

Turning is where you tune your barrel's best harmonic "node" to a particular favorite load (using a factory round).

Both methods try to achieve the same results, but from different angles, under two different conditions (factory vs non factory).

BUT...combining reloading and tuning together will give your rifle such an accuracy 'edge' you'll be saying "my rifle is more accurate than I am".

We all have good/bad days of shooting. I was advised by RAS Tuner (the 'misleading and incorrect information' people)...once you get your 'heavenly perfect' load developed...that you shoot a volley of 10-12 2-shot groups and then take an average. This will help smooth out the 'good/bad' human factor of shooting and give you a more realistic picture of your ability of shooting your 'heavenly perfect' load.

You are now ready to shoot the longer distances for more refinement until you reach your accuracy goal.

NOW...it's time for you to shoot your 10 shot groups into one ragged hole (on one of those 'good' days, if course!)

 

[Rich Coyle]

dwinmeade,

Your assumption that one uses a tuner for factory loads and reloading to accomplish the same thing is flawed. On two different rifles I worked up to pressure and then tuned the barrel with the adjustable brake. Once the tuner is tuned one can then fire as many rounds as they want and the group will be about as good as that rifle can shoot. I have done the same thing with the Sims vibration barrel donuts.

If it doesn't fire two close it is not going to fire three close.

 

[HRM Johnny]

Has anyone tried the tubbs tunable break?

 

[Bart B]

dwinmeade,

Your assumption that one uses a tuner for factory loads and reloading to accomplish the same thing is flawed. On two different rifles I worked up to pressure and then tuned the barrel with the adjustable brake. Once the tuner is tuned one can then fire as many rounds as they want and the group will be about as good as that rifle can shoot. I have done the same thing with the Sims vibration barrel donuts.

If it doesn't fire two close it is not going to fire three close.

Competitive rifle shooters have used tuners with factory loads for decades, both rim and center fire match ammo.

All barrels don't vibrate at the same resonant and harmonic frequencies for a given cartridge load. Tuners adjust those frequencies to best compensate for that load's muzzle velocities by making slower bullets leave at higher angles than faster ones.