Too much neck tension

Dildobaggins

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  • Jun 26, 2020
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    New to reloading so bare with me. So there is an antlerless season in upstate NY this week. Figured I'd try and get some loins for the freezer. I have zero ammo other than .223. I quickly ordered Forster dies for my 6.5 Grendel (FL and seater) And case trimmers etc. I did not buy a mandrel for this one. Slipped my mind.

    While doing some FL sizing on some once fired brass I was getting consistent neck tension diameter of .260. seating the bullets felt rather hard. They didn't slip in like they do with my 6 creed or 223.

    Is .04 neck tension too much? This is for an AR in 6.5 grendel btw.
     
    New to reloading so bare with me. So there is an antlerless season in upstate NY this week. Figured I'd try and get some loins for the freezer. I have zero ammo other than .223. I quickly ordered Forster dies for my 6.5 Grendel (FL and seater) And case trimmers etc. I did not buy a mandrel for this one. Slipped my mind.

    While doing some FL sizing on some once fired brass I was getting consistent neck tension diameter of .260. seating the bullets felt rather hard. They didn't slip in like they do with my 6 creed or 223.

    Is .04 neck tension too much? This is for an AR in 6.5 grendel btw.
    .260 brass is going to have thicker brass than a .223 and just a little thicker than a .260 (depending and the brand, could be even more thick that you'd expect). So, .004 neck tension is somewhat stiff and you'd probably need to make sure the neck is lubed. . . especially if it pristine clean.
     
    OP said .04. Forty thousands, not four thousands
    Yeah, but he also said 0.260, so I assume he's saying his neck ID is 0.260", or 0.004" under.

    OP, assuming that's correct, is there a decent inside chamfer on the case mouth? I've seen dramatic improvements in bullet seating resistance/issues by putting an inside chamfer on.
     
    Agree.
    OP should double check his post. Likely he slipped digit reporting neck tension.
    Assuming the 0.004" is what he really has, I would heed the advice about a good ID chamfer and then start backing off the neck tension till you achieve a reasonable seating force.
     
    Best way to measure neck tension is with pin gauges, but most don’t bother with that. Just measure the OD of the neck before seating, then measure it again after seating. The difference is your tension. Write down the measurement of the seated neck OD, it’s useful to know long-term, such as if you want to get that Forster die honed (you should).
     
    Correct me if I am wrong but Edds question was WHAT are you measuring (neck OD?) not WITH WHAT are you measuring.
    My bad, I'm measuring neck ID. Kinda just wondering if it's safe to shoot with that much tension. I'd like it to be accurate but I'm looking for minute of deer at this point. I feel like I remember reading somewhere on this forum that Hornady will sometimes use .004 neck tension and that's why they don't crimp. That was for 223 I believe
     
    My bad, I'm measuring neck ID. Kinda just wondering if it's safe to shoot with that much tension. I'd like it to be accurate but I'm looking for minute of deer at this point. I feel like I remember reading somewhere on this forum that Hornady will sometimes use .004 neck tension and that's why they don't crimp. That was for 223 I believe
    .004 shouldn’t be dangerous assuming you arent silly with the powder charge and cases are all sized appropriately but i run .002-.003 for all center fire rifle cartridges (no crimping on anything)
     
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    I'm using a micrometer to measure inside diameter of the neck. I know this isn't the most accurate way. But I'm using what I have in hand.
    Just FYI, for in the future if you have to discuss reloading again...

    There are terms we use for inspection instruments and tools that are often traditional rather than technical, similar to the way we call the neck ID "neck tension" when it really isn't force but it is the neck ID.

    There are micrometers, and calipers. This is just traditional language.

    https://toolguyd.com/calipers-micrometers-differences/

    If you used the inside jaws of a 6" micrometer caliper, then just call it a caliper.

    An inside micrometer exists, but I doubt that is what you are using.

    Keep an eye on those kiddos, they are more expensive than brass....
     
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    0.004' of neck tension should be way too much. 0.002' is the 'theoretical' maximum, is which you will have neck tension. all over that you will deform your brass and your bullet and no additional neck tension will be applied.


    With a .30 caliber bullet and hard brass, we hit it around 0.0015" of neck tension. .22 caliber bullets can only handle .001" of neck tension before yielding.
     
    Went out and shot today. Those rounds with that neck tension did alright. Only did 2 different charges. Used H335 at 27.0 and 27.2 grains. With 120 gr eldM. Either load will suffice for this coming week, until I get a mandrel for it.View attachment 7952808
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    IMG_20220908_154651~2.jpg
     
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