Sherman Tank Tank's Rifle Shop
 
 

Rifling Twist Calculator

This calculator operates by the Greenhill Formula.  The Formula for this calculator is setup for Copper Jacketed Lead Core Bullets Only.

Caliber (.xxx"):
"

Bullet Length:
"

Velocity Value1:

Bullet Twist:
1-"

Note 1: Velocity Value-  Enter the following value which corresponds to the bullet's muzzle velocity.

Velocity                    Value

up to 1000fps              48
1000-1499fps             125
1500-2999fps             150
3000-4500fps             180