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Thread: .223 and 40gr projectiles. COAL differences.

  1. #1
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    .223 and 40gr projectiles. COAL differences.

    Good evening,
    I usually load 52gr SMK or A-Max but have recently been trying the Hornady 40gr V-Max (with N133) and am finding considerable differences in the COAL suggested by the various reloading manuals and powder/bullet manufacturers.

    Vihtavuori: 2.075"
    Lee: 2.165"
    Sierra: 2.175"
    Hornady: 2.2"
    Lyman: 2.215"
    Sierra 2.25"

    I'm not convinced that the Vihtavuori figure can be correct as it is so much shorter than all the others and would, I think, result in a very compressed load.

    Any thoughts please? I have been loading to 2.23" with reasonable results, but cannot go any lower as there is insufficient adjustment on the Lee seating die. I could turn up a slightly different insert for the seating die to get me to shorter COAL but am wondering whether there's any point.

    Questions really are (a) whether the Vihtavuori data is incorrect, and (b) whether there's any benefit to seating to give COAL of 2.2" or less with a 40gr bullet, in particular 40gr V-Max?

  2. #2
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    Have you tried pushing Un-primed case into the breach with a bullet in the case close the bolt then open it push the bullet back out with a cleaning rod then push in in a couple of tho ----my book says col 2.260"---I load my .223 with 24.5grns of ramshot "tac" col 2.224" this works for me with sub inch groups I have also used 22grn of tac for sub 50yard rounds

  3. #3
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    I load blitzkings to 2.260"
    Thanks for looking

  4. #4
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    Thanks guys. That's helpful. I'll just stick with the longer COAL which works well enough for me rather than go too short.

  5. #5
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    Quote Originally Posted by severnsider View Post

    (a) whether the Vihtavuori data is incorrect?
    Each reloading company will give the values they themselves have tested and decided is safe. No doubt if you wrote an entry you'd give a different value.
    Good deals with: svincett, dave milne, Muskett, Dreben, roger.kerry, TALL, Helidave1, Chelseablue, Leeroy7031, Mousemann, pnuk, Practical, NEWFI, HOOGS, Webb22, lazybones1416 and deanw5262 among others. Thanks Guys.

  6. #6
    Parabuteo is offline My Chrony has bought it a couple of times...
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    I would never read too much into OALs as it is such a moveable goalpost.

    If you look a the SAAMI spec for the cart it will invariably be different to various manufacturers figures. In my case life is fairly simple as all of my rifles (1 No4 and 3 ARs) are all mag fed, so the best OAL is mag length and then mess with the load for the harmonics.

    In some ways you can cheat the effects of variable seating depth (or at least seating into the landes) by crimping, and we would not want a bullet that is being thumped into a chamber via a splined barrel extension to have too long a seat anyway.

    Different to hunting I know, but the point is that there are many variable to mess with, so dont worry too much. There is usually a way
    I'm a maggot in another life you know

  7. #7
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    Quote Originally Posted by Parabuteo View Post
    I would never read too much into OALs as it is such a moveable goalpost.

    If you look a the SAAMI spec for the cart it will invariably be different to various manufacturers figures. In my case life is fairly simple as all of my rifles (1 No4 and 3 ARs) are all mag fed, so the best OAL is mag length and then mess with the load for the harmonics.

    In some ways you can cheat the effects of variable seating depth (or at least seating into the landes) by crimping, and we would not want a bullet that is being thumped into a chamber via a splined barrel extension to have too long a seat anyway.

    Different to hunting I know, but the point is that there are many variable to mess with, so dont worry too much. There is usually a way
    Thanks for that. Yes, I'm going to carry on using the SAAMI length. I was just particularly surprised at the very short OAL suggested by Vihtavuori. I'm not going to try it!

  8. #8
    Parabuteo is offline My Chrony has bought it a couple of times...
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    Quote Originally Posted by severnsider View Post
    Thanks for that. Yes, I'm going to carry on using the SAAMI length. I was just particularly surprised at the very short OAL suggested by Vihtavuori. I'm not going to try it!
    If I tooks right...It probably is right chap. The thing is that the charge weight alone can hugely change the harmonics. On my old Dolphin (remember the green piece of Mecano?) it was almost precisely 0.6gr between nodes. The group used to tighten up around those weights.

    Russell Simmonds proved a point be seating the bullet deeply (about 50 thou deeper) and it shot the same. It often depends how twangy the barrel is to start with I guess

    People often get tied in knots trying to wring the nth degree of group size out of a load, manage it once when the stars were aligned, and burn a barrel out trying to defy physics, when they may do better settling on a stable and predictable load and burn a barrel out practicing positional or wind reading.
    I'm a maggot in another life you know

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