Q: I’ve noticed that a lot of people have been led to believe that long, slender projectiles such as the .277 calibre are less accurate at 100m than at 200m, as the “bullet goes to sleep”. I have even read this statement written by some gun writers in Australia.
I understand that longer bullets go through yaw for a slightly longer period which is why they need a faster rifling twist.
However, once the bullet leaves the barrel, it is on a set trajectory path, so as the distance doubles so does the projectile’s spread. Would you be able to clarify this for your readers, please?
Mathew Jamieson
A: The length of a projectile, not the weight, determines how fast a rifling twist is needed to stabilise it. I have never heard any mention of long .277 projectiles in this regard as the standard 1:10” twist is fast enough to stabilise even long 160gn .277 bullets.
Usually, this is mentioned with connection to long, slender .264” (6.5mm) bullets. The heaviest ones are notorious for yawing after they leave the muzzle and don’t go to sleep until after they reach the 200m mark.
In my experience with 6.5 bullets they often do shoot tighter groups at 200m than they do at 100. I hope this satisfies your curiosity.
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