Caliber Twist Rates

The recommended twist rate to stabilize various bullet weights at normal velocities.

NOTE: This may not hold for heavy rifle bullets fired at subsonic velocities.

Calibre

Twist Rate

Bullet Weights
.172

1:9

1:10

For bullets heavier than 30 gr

For bullets up to 30 gr.

.204/20 1:12 For all bullets
.222 Rim Fire

1:14

1:16

1:17

Twist for pistol barrels

Standard twist for rifle barrels

Special twist for rifle barrels

.224 Center Fire

1:8

1:9

1:12

1:14

1:15

1:16

For bullets heavier than 70 gr.

For bullets up to 70 gr.

For bullets up to 63 gr.

For bullets up to 55 gr.

For bullets up to 55 gr. driven 4,100 fps or more

For bullets up to 55 gr. driven 4,300 fps or more

6mm/.243

1:8

1:10

1:12

1:13

1:14

1:15

Special for VLD bullets over 100 gr.

For bullets up to 120 gr. and VLD under 100 gr.

For bullets up to 85 gr.

For bullets up to 75 gr.

For bullets up to 70 gr.

Special for bullets up to 70 gr.

.257

1:9

1:10

1:12

1:13

1:14

For bullets heavier than 100 gr.

For bullets up to 100 gr.

For bullets up to 90 gr.

For bullets up to 80 gr.

For bullets up to 70 gr.

6.5mm/.264

1:8

1:9

For bullets heavier than 130 gr.

For bullets up to 130 gr.

.270 1:10 For all bullets
7mm/.284

1:9

1:11

For bullets heavier than 140 gr.

For bullets up to 140 gr.

.308

1:8

1:10

1:12

1:14

1:15

For bullets heavier than 220gr.

For bullets up to 220 gr.

For bullets up to 170 gr.

For bullets up to 168 gr.

For bullets up to 150 gr.

7.65mm/.311 1:10 For all bullets
8mm/.323 1:10 For all bullets
.338 1:10 For all bullets
9mm/.355

1:14

1:16

For low-velocity wadcutters

For all other bullets

.38/.357

1:14

1:18

For low-velocity wadcutters

For all other bullets

.358 1:14 For all bullets
.375 1:12 For all bullets
10mm/.400 1:16 For all bullets
.411 1:14 For all bullets
.416 1:14 For all bullets
.44

1:20

1:16

For all bullets

For low velocity wadcutters

.451 1:16 For all bullets
.458 1:14 For all bullets