Nice looking bullet Dellet and I tend to agree with you on stability. Having a bullet of that design for a 14 twist the rule of thumb based on how I was taught. To do what it is I am thinking you are trying to accomplish would be for it to be around .864 in length and being closer to the 134gr. weight range.

Caliber      0.286      Inches            
Bullet Weight      152      Grains            
Bullet Length      1.01      Inches            
Barrel Twist      14      Inches/turn            
muzzle velocity      1470      fps            
Temperature      50      degrees Fahrenheit (59 is standard)            
Pressure      29.92      inches of mercury (29.92 is standard)            
                       
Sg =      1.36                  


Yup the longer 152 grain would be unstable when the weather changed or when the velocity was too slow.

You should have a tighter twist to shoot it or use a shorter lighter bullet as John suggests.


Caliber      0.286      Inches            
Bullet Weight      130      Grains            
Bullet Length      0.86      Inches            
Barrel Twist      14      Inches/turn            
muzzle velocity      1470      fps            
Temperature      50      degrees Fahrenheit (59 is standard)            
Pressure      29.92      inches of mercury (29.92 is standard)            
                       
Sg =      1.83                  

I like that 130B bullet better than the NOE but, I hate their min meplats of .180. It would be much better, balistically with a .08 - .100 meplat.

If you get the 130B, have them make the first band, .282, it will help with BSing.

Frank

Below 1.4 the quality of the bullet makes the difference.


It is not the quality of the bullet - it is the length of the bullet.
If it is too long for your barrel's twist to gyroscopically stabilize it; it will not be spinning fast enough and will tumble.
It may tumble immediately or a short distance down range and more so if the weather is colder or the atmospheric pressure is higher.

Truer words could not be spoken: " From personal experience. " All though there are several programs out there that seem to be providing good, honest and trusted information. My own personal experience has proven that it has not always been so and one can end up purchasing the wrong bullet design to fit his or her needs. If you can come across someone who is already doing what it is you are wanting to accomplish and having great success. I have found it is has been by far the better way to achieve the same type of success.

frnkeore wrote on Dec 16^th, 2018 at 5:02pm:


This is why I say bullet construction or shape can allow for a larger window of stability.

The problem with radial grooves in a bullet is that they will actually speed up the air moving over the bullet at that point. When you get into the trans sonic speeds you get turbulence at the grooves that tend to be at the base. The nose can be sub sonic not creating a shock wave, the base can be super creating a wave off the grooves. This idea has actually been filmed.

About the 5 min mark.
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One of the things I am finding out shooting subsonic is the amount of in flight bullet noise there is. Noise is basically turbulence. Turbulence causes instability. Unless you have a program that can simulate a wind tunnel, the stability calculators will not factor in bullet shape.

Guys that can get cast bullets flying well in some ways beat science all to death. They knew what worked well 100 years ago, in some ways science is just now explaining what the smart guys simply figured out worked.

It’s that knowledge base I’m hoping to tap into.

Dave who's comments are you referring too and what was the information being shared.

Pretty simple.

Ballisticians state it is impossible to have dynamic stability until you first have gyroscopic stability.

So you need the proper selection of bullet length for your barrel twist before it will be gyroscopically stable.

No bullet shape will restore a bullet that is  gyroscopically unstable.