Bullet Seating Depth Variations

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    I am having some inconsistencies in my C.O.A.L and am curious if I am being too anal or what I might be doing wrong to get inconsistencies. I have trimmed all my cases to 1.750" and am using Hornady 75gr BTHP and SMK 69gr bullets. I am getting variations between .002 and .003 and even one .007. I am sure that the case lengths are all the same. I am using a Hornady AP press and die. I'm guessing its a die issue but seeking advice. Forgot to mention, reloading .223
     

    bohica793

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    Unless you are shooting long range competition, I think you are being overly concerned. The variations can be caused by loose die in the press, dirty die, bullet variations, etc. If you are using a turret press, the turret itself will shift slightly when applying the stroke to seat the bullet. Unless you are using a single stage press with precision seating dies, you will always see a variation. As long as you are longer than minimum OAL and short enough to properly chamber and feed from the magazine, you should be golden.
     

    16gauge

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    Sounds like your okay, with all the potential things that can affect the C.O.A.L. the only other way to measure is with a bullet comparator like one that Forster makes. It measures from the ogive of the bullet not the tip. No matter what load consistency and group size are the ultimate factors to check a load.
     
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    I use a comparator from hornady. It can be a pain to measure each bullet and separate. But u will only adjust the die for each group of bullets. In the long run u will end up with a consistent jump. From where the paper will tell u if ur rifle likes that seating depth. Then a whole new ladder begins.
     

    Va boy

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    I run a Hornady LNL AP progressive. If I run the last round through the dies by itself, I get seating depth variations greater than what I consider normal for projectile inconsistency (pistol). But when I run a full set of cases along with the last cartridge, its more consistent. All hardware is tight. I chalk it up to machine flex.
     
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    latch

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    hmmm....do mongo's gun go bang? do zombies in mongo's yard fall down?

    mongo happy.
     

    Marquezj16

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    Your inconsistencies are normal variations. 7 thousandth of an inch is fair. As others have pointed out, there are several factors that could affect it. I would not worry too much about it. What's important is how your rifle likes the load.
     
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