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Posted: 3/26/2013 7:28:39 PM EDT
[Last Edit: John87][Edited]
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This variability is why I load my magazine length rounds a bit shorter than many others.
You checked four rounds and found 9 thousandths difference. Imagine what the real variation within the lot is (hint - probably even more). I load my 223 rounds to a nominal 2.235" OAL. I don't want the longest bullets causing a jam. The other thing I do is make sure the slant height of the loaded round is smaller than the magazine. For a 223 round, the slant height is about 7 thousandths longer than the OAL. This ensures that a round that tips in the magazine does not hang up and get jammed. Enjoy! |
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What is the variation of those 5 rounds when measured from the ogive?
I'm willing to bet (not very much) the ogive variation is smaller than the COAL variation. |
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Originally Posted By bags533:
What is the variation of those 5 rounds when measured from the ogive? I'm willing to bet (not very much) the ogive variation is smaller than the COAL variation. This is what really matters and I have done some base to ogive measuring and found that it can vary as much as .009 as well. |
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Originally Posted By Muddydogs:
Originally Posted By bags533:
What is the variation of those 5 rounds when measured from the ogive? I'm willing to bet (not very much) the ogive variation is smaller than the COAL variation. This is what really matters... It's not what matters for rounds which have to fit and feed from a magazine. For magazine-fed rounds, the rounds have to fit ine the magazine and have a little roo to move around without binding up. To prevent binding, you need to ensure the longest bullet does not bind. |
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Originally Posted By bags533:
Any update? No, I'm not impatient.  If I go to the range this weekend there will be. Right now its doubtful. I CAN shoot a rifle on my property, I just don't like to. Damn people and those wooden boxes they live in 
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Originally Posted By John87:
Originally Posted By bags533:
Any update? No, I'm not impatient. If I go to the range this weekend there will be. Right now its doubtful. I CAN shoot a rifle on my property, I just don't like to. Damn people and those wooden boxes they live in Was curious about the variation in regards to measuring these rounds from the ogive. |
The Marines I have seen around the world have the cleanest bodies, the filthiest minds, the highest morale, and the lowest morals of any group of animals I have ever seen. --Eleanor Roosevelt
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Originally Posted By bags533:
Originally Posted By John87:
Originally Posted By bags533:
Any update? No, I'm not impatient. If I go to the range this weekend there will be. Right now its doubtful. I CAN shoot a rifle on my property, I just don't like to. Damn people and those wooden boxes they live in Was curious about the variation in regards to measuring these rounds from the ogive. that, that I can do. |
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If not already, this should be linked in the "useful threads" tacked thread. This is great information for new reloaders. I've seen the COAL question come up many, many times, and this is a great write-up. Thanks, John87 |
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Thanks John, it appears my suspicions were correct.
The variation of COAL when measured from the ogive from quality bullets is much less than the variation of the total round COAL. Very important to know and understand. Thank you for providing proof for this fact. I agree with tbonifie, that this should be part of the 'useful threads'. |
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Originally Posted By bags533: Thanks John, it appears my suspicions were correct. The variation of COAL when measured from the ogive from quality bullets is much less than the variation of the total round COAL. Very important to know and understand. Thank you for providing proof for this fact. I agree with tbonifie, that this should be part of the 'useful threads'. That's why I set the toggle to keep this thread out of the archives. OP knows as I sent him an IM.
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Originally Posted By dryflash3:
Originally Posted By bags533:
Thanks John, it appears my suspicions were correct. The variation of COAL when measured from the ogive from quality bullets is much less than the variation of the total round COAL. Very important to know and understand. Thank you for providing proof for this fact. I agree with tbonifie, that this should be part of the 'useful threads'. That's why I set the toggle to keep this thread out of the archives. OP knows as I sent him an IM. its in the tacked thread as well
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For those who may not know, If you place a link to a thread in the tacked "Useful info thread", the archive toggle must be set. (must be a hot link) Or the link will die when thread goes into the archive. If you have a worthy thread, you need to IM me or AeroE to set the archive toggle for you. May not happen for every thread, but you can ask. Be sure to look that thread over so as not to post dupes. If you don't know how to hot link or post pics, instructions are up in FAQ's. |
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For what its worth, when I reload for my precision rifle I sort the projectiles by the length of their bearing surface - the part of the bullet that makes physical contact with the bore. In a lot 500 175 gr matchkings, the variation between the longest and shortest projectiles was 0.015". These are 'match' projectiles, so I would guess that in large batches of just about any type of bullet you would see a similar variation percentage.
I should include the fact that there were only a select few that measured in those extremes. They usually wind up concentrated around one or two measurements, and you can see the distribution bell curve pretty easily. But yeah, measuring from the ogive is a much more reliable route, especially if you don't have to worry about magazine dimensions and whatnot. |
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