Originally Posted by
lemoyne
Semisane
According to both my experiments and the numbers using the formula for twist to bullet length the 1-28 and the 1-24 should do quite well with the 41 cal 210 gr bullet.
The 1-20 twist figures out to shoot something like a 38 caliber 210 to 240 gr bullet or a 250 or 275 gr 40 caliber bullet depending on the construction of the bullet we are talking about lead jacketed bullets here the brass or copper bullets are longer for weight so would be lighter at the right length. { just my 2 cents}
Lee... Question??
Using the 1-20 twist shooting the shorter bullets should create a problem called 'Over Stabilization' which really is not a problem as I understand it
IF the bullet can can handle the faster spin rate.
From the reading and writings that I have read... 'over stablization' (spinning the bullet to fast) along with the accellerated velocity really creates 'wobble' in a less than perfectly round and balanced bullet. This wobble then causes loss of accuracy.
Is this not one of the reasons that you can not accurately shoot a PRB from a fast twist bore with out reducing the charge to slow the ball down?
I do not have the article available to me on this computer that discusses this but I will look for it on my base computer.
Found this quote...
A term we often hear is "overstabilization" of the bullet. This doesn’t happen. Either a bullet is stable or it isn’t. Too little twist will not stabilize the bullet, while too much twist, with a couple of exceptions, does little harm. Faster than optimum twists tend to exaggerate errors in bullet concentricity and may cause wobble. The faster twist also causes the bullet to spin at higher rpm, which can cause bullet blowup or disintegration because of the high centrifugal forces generated. For example, the .220 Swift, at 4,000 fps., spins the 50-grain bullet at 240,000 rpm