Author Topic: Question on barrel twist rate (Read 407 times)

longwinters · « **on:** March 30, 2005, 12:05:22 PM »

Does barrel twist rate effect bullet velocity? I understand that it possibly can effect the stability of the bullet depending on bullet weight but how about velocity at the muzzle?

Long

KN · « **Reply #1 on:** March 30, 2005, 06:10:18 PM »

I would imagine it would. Consider how hard it would be to push a bullet down the barrel if you had no twist at all. Then consider that it has to spin down the same barrel with a twist. The more it has to spin the more power it would take to push it. The more twist, the more spin. KN

ricciardelli · « **Reply #2 on:** March 30, 2005, 07:53:08 PM »

Twist rate will determine the rotational velocity of the bullet, however, I do not believe it has any effect on the forward velocity.

earschplitinloudenboomer · « **Reply #3 on:** March 30, 2005, 08:24:42 PM »

By virtue of having to contend with a miniscule amount more surface area before exiting the muzzle of a barrel with a fast twist (barrel lengths being equal) there could be a difference. I do not feel that it would be measurable with commonly available equipmemt.

longgun · « **Reply #4 on:** March 31, 2005, 03:45:42 AM »

Last summer I was in Raton N.M. and was talking with Bo Clerke a barrel maker there in Raton. I mentioned this to him about velocity and barrel twist. He quoted some mathematics which stated the velocity would be the same in fast or slow twist barrels. I mentioned that I had chronographed fast twist and slow twist 22 cal barrels and the fast twist had slower velocity. To this he said that there were other things to consider from one barrel mfg to another that would cause this but that barrel twist was not one of them. don