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308 cal 1-10 or1-12 twist

rdmorserdmorse Member Posts: 2 ✭✭
edited December 2007 in Ask the Experts
looking for 308 cal remington&winchester have 1-10,weatherby 1-12 would like to know which is the best.will be shooting 165 & 168gr. bullets
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  • JustCJustC Member Posts: 16,056 ✭✭✭
    edited November -1
    1:10 will spin any weight,..1:12 will stop somewhere near 200gr +/- pills. If you plan on NOT going higher than 168gr, then the 1:12 will be fine.
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  • jtmarine0831jtmarine0831 Member Posts: 908 ✭✭✭✭
    edited November -1
    This should help a little!
    But JustC is right on the money!


    Products::Rifle Barrels::Calibers and Twists

    The information below will help you select the best barrel twist for your specific needs, providing of course there are multiple choices. If you'll be shooting one bullet weight, choose a twist from the chart just fast enough to stabilize it. Too fast a twist simply overspins the bullet and may result in reduced accuracy. On the other hand, a twist too slow for any bullet will likely produce instability, keyholing and rotten accuracy. So if you're going to be using several bullet weights, be sure to select a twist that will stabilize the heaviest one, since lighter bullets will also be stabilized.

    By way of explanation, the numbers in the "Twist" column indicate how far the bullet must travel through the bore to make one full revolution. This is determined by the rate of rotation of the rifling. For example, a 9"-twist barrel spins the bullet one full turn when it passes 9 inches through the bore. In a 16"-twist barrel, the bullet makes one revolution in 16 inches. So at the same bullet velocity, the 9" twist is faster (spins the bullet faster) than the 16" twist. Consequently, as the chart reflects in the .224 CF section, the 9" twist is necessary for stabilizing heavier bullet weights.

    Again looking at the .224 CF section, if you're planning to shoot 55-grain bullets, the 14" twist is ideal. This twist is also the best choice for 52- and 53-grain match bullets driven at moderate velocities. But if you're also contemplating shooting a 60-grainer, go with the 12" twist, since it will stabilize all the bullets you'll be using. As you can see from the 15" and 16" twists, higher velocities also spin the bullet faster and may enable a slower-than-recommended twist to stabilize a marginally overweight bullet. However, this is tricky stuff best left to those who are highly experienced in operating at the ragged edge of stability and sanity.

    The basic principles just outlined apply to all the calibers below.
    But, if you have questions or need a recommendation, let us know.




    Caliber Twist:


    .172
    - 9" for bullets heavier than 30gr.
    - 10" for bullets up to 30gr.

    .204/20
    - 9" for VLD bullets
    - 10" for bullets up to 50gr.
    - 12" for bullets up to 40gr.


    .222 RF
    - 10"* 60 gr. bullets Ratchet rifled 4 groove
    - 14"* Twist for pistol barrels
    - 15"* Special twist for rifle barrels
    - 16" Standard twist for rifle barrels
    - 16"* Ratchet rifled 4 groove
    - 17"* Special twist for rifle barrels

    .224 CF
    - 7" for bullets heavier than 80gr.
    - 8" for bullets up to 80gr.
    - 8"* Ratchet rifled 4 groove
    - 9" for bullets up to 70gr.
    - 12: for bullets up to 63gr.
    - 14" for bullets up to 55gr.
    - 14"* Ratchet rifled 4 groove
    - 15"* for bullets up to 55gr. driven 4,100 pfs or more
    - 16:* for bullets up to 55gr. driven 4,300 fps or more

    6mm/.243
    - 8" Special for VLD bullets over 100 gr.
    - 8"* Ratchet rifled 4 groove
    - 10" For bullets up to 120 gr. and VLD under 100 gr.
    - 12" for bullets up to 85gr.
    - 13"* for bullets up to 75gr.
    - 14"* for bullets up to 70gr.
    - 14"* Ratchet rifled 4 groove
    - 15"* Special for bullets up to 70gr.

    .257
    - 9" for bullets heavier than 100gr.
    - 10" for bullets up to 100gr.
    - 12" for bullets up to 90gr.
    - 13"* for bullets up to 80gr.
    - 14"* for bullets up to 70gr.

    6.5mm/.264
    - 8" for bullets heavier than 130gr.
    - 8"* Ratchet rifled 4 groove
    - 9" for bullets up to 130gr.

    .270
    - 10" for all bullets

    7mm/.284
    - 8" for all bullets-customer discretion 180 gr. VLD
    - 9" for bullets heavier than 140gr.
    - 11" for bullets up to 140gr.

    .307
    - 13"* Special size and twist

    .308
    - 8" for bullets heavier than 220gr.
    - 10" for bullets up to 220gr.
    - 12" for bullets up to 170gr.
    - 13"* Ratchet rifled 4 groove
    - 14"* for bullets up to 168gr.
    - 15"* for bullets up to 150gr.
    - 17"* for bullets up to 125 gr.

    7.65mm/.311
    - 10" for all bullets

    8mm/.323
    - 10" for all bullets

    .338
    - 8" for all bullets
    - 10" for all bullets


    9mm/.355
    - 10"* Special
    - 14" for low velocity wad cutters
    - 16" for all other bullets

    9.3mm/.365
    - 12" for all bullets

    .38/.357
    - 14" for low velocity wad cutters
    - 18" for all other bullets

    .358
    - 12" Special
    - 14" for all bullets

    .375
    - 12" for all bullets

    10mm/.400
    - 16" for all bullets

    .411
    - 14" for all bullets

    .416
    - 14" for all bullets

    .44
    - 20" for all bullets
    - 16" for low velocity wad cutters

    .451
    - 16" for all bullets

    .458
    - 14" for all bullets


    * Stainless Steel only




    Black Powder Barrels (1.250" x 30"):

    .32
    - 14", 16" .320 groove

    .38
    - 18" .377 groove

    .38
    - 20" .379 groove

    .40
    - 20" .403 groove

    .457
    - 20" , 14" .457 groove




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