Case Neck Tension
00:57:49 | From the book: Modern Advancements in Long Range Shooting Volume 2, Chapter 6 – Neck Tension. We explore the complexities of neck tension, what it means to handloaders, practical considerations, and what our testing showed to be promising and what didn’t seem to matter.
Hi,
Is there a problem with the Neck Tension audio from 44:03 onwards ?
Hello Robert-
Thank you for the heads up, we have corrected the audio and you should be all set now!
Hi,
What is relation between neck tension (heavy or light) vs accuracy ? Have you done some test in this dirrection ? Sorry , I didn’t heard nothing in the podcast, maybe I have missed..
Thank you!
Cristi
We have done testing on this and haven’t found any relationship between neck tension and groups UNLESS neck tension is so heavy that you damage bullets when seated. Such heavy neck tension also often results in high CBTO variation. Neither of those things are good, although we have not directly confirmed that they make groups bigger.
Take care,
-Bryan
Have you done any testing on headspace vs poi change?
Only indirectly; in the sense that Removing/Replacing barrels on Savage actions results in headspace not being 100% repeatable. We haven’t noticed precision being greatly affected by this, but we haven’t tested specifically for it either. Those guns are assembled to shoot for radar tests to characterize flight performance and we usually don’t even look at groups beyond verifying the bullets are stable and flying good enough to characterize drag. In the tests where we are looking at groups, it doesn’t seem to matter what the exact headspace is as long as it’s between the GO and NOGO gauge.
-Bryan
Bryan, after listening to these and reading the book, is velocity SD the only thing that handloading affects to precision? Not including damaging the bullet when seating.
Jay,
To be strictly technical, the SD of velocity and the SD of the bullets BC are two factors you control with handloading that affect precision (groups) at long range.
Other things you control as a hand-loader can affect precision beginning at short range (100 yards) such as bullet seating depth (jump).
Consistency is known to be a good thing for precision, but there are some variables that are more conditional than others, like neck tension. There may be applications where neck tension really affects groups, but when directly tested to a statistically significant degree, neck tension and many other variables have been determined to not affect precision.
Check out the podcast/Chapter on TOP Gun which talks more about our Theory Of Precision being mostly driven by the gun weight to bullet KE ratio.
Take care,
-Bryan
Thanks Bryan! That was the kind of answer that I was hoping to get.
Without a force gauge the most reliable way to check neck tension is with pin gauges, at least that we have found in BR.
Without a force gauge the most reliable way to check neck tension is with pin gauges, at least that we have found in BR.