223 Rifle Twist Chart - Vista Outdoor

[Pages:2]Maximum Bullet Length (in.)

1.600 1.500 1.400 1.300 1.200 1.100 1.000

223 Rifle Twist Chart

Example:

A proposed 69 grain match bullet is pulled from the case, and measured for length with a caliper. The bullet is .900" long.

The .900" value is followed to the right until it intersects the minimum twist requirement line.

The twist required would be 1 : 8.3 or faster.

Since no rifles are chambered in 1:8.3, a twist of 1:8 or faster would be required to shoot this bullet.

0.900

0.800

0.700

0.600

0.500

Assumptions: Based on Greenhill's Equasion, velocity less than 2800 fps, using copper jacketed lead bullets.

0.400

5

6

7

8

9

10

11

12

13

14

Twist Rate of Barrel ( 1 : Inches per Revolution)

Prepared by Durham, Ernest 4/8/2008

Page 1

Bullet Twist and Maximum Bullet Length Based off the Greenhill Equasion

Rifle Twist Rate ( Inches for one full revolution) 5 6 7 7.5 8 8.5 9 10 11 12 13

Maximum Bullet Length 1.492 1.243 1.066 0.995 0.932 0.878 0.829 0.746 0.678 0.622 0.574

0.223 150 0.223 150 0.223 150 0.223 150 0.223 150 0.223 150 0.223 150 0.223 150 0.223 150 0.223 150 0.223 150

 ................
................

In order to avoid copyright disputes, this page is only a partial summary.

Google Online Preview   Download