Originally Posted by
Gun Nut
There is a yaw shown in Lyman Reloading Handbook 45th Edition. The yaw imparted to the bullet during the spinning around the axis of flight may be caused by excessive velocity or the wrong combination of twist to bullet length. Bullets that yaw in this manner in early flight sometime settles down and spin true as they lose velocity.
They use the term “yaw” I called it wobble. A bullet when it leave the muzzle may not stabilize immediately, there are a number of factors that can cause this to happen the illustration mention a few. Eventually they usually stabilize and fly true. The distance it take this to happen can vary from gun to gun and possibly from one bullet design to another. I mention my .303 British it seem to take about 100 yards with the bullet I was using to stabilized. At one point I was loading a cast spiral tip with the recommended Unique load of powder. The bullet was key-holing at 25 yards. I switch to a reduced powder charge of IMR 4895 and it stop the bullet from key-holing. The general accept idea is they put rifling in the bore in order to spin the bullet which off-sets the influence of gravity. What I discovered was spin has another variable which is velocity. The speed that the bullet travels through the rifling determines its rpms. If the rpms are not adequate the bullet will not stabilize and will end up tumbling, If its rpms are a bit high it will yaw, but as the bullet slows in flight it generally stabilizes. I’m not a ballistic expert, so there maybe other factors involved.
You don’t stop hunting because you grow old. You grow old because you stop hunting.
- Gun Nut