September 3, 2020, 11:31 PM | #26 |
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It's Minute Of Angle. Settled that one!
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September 4, 2020, 08:43 AM | #27 |
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....but does that relate to accuracy or precision?
Most gun folks know what MOA is. Most relate it to a group size of 1" or less at 100 yards. Quite simple really, but there's always that one or two persons that has to complicate the whole deal with theorems and the chastising of calling it "accuracy" instead of "precision". I was making a joke relative to this. Thanks for being so "accurate". ....or was it being "precise"? |
September 4, 2020, 10:57 PM | #28 |
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Yes, I realized it was humor and tried to respond in kind. It's difficult to get that kind of thing across sometimes.
MOA is a unit of measure that can be used to measure EITHER accuracy or precision, however either one is defined.
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September 6, 2020, 04:02 PM | #29 |
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I want to piggyback off COSteve's distinction between mechanical accuracy and practical accuracy.
A rifle capable of 1 MOA accuracy, shot by a shooter capable of holding 1 MOA accuracy will still put bullets outside of that 1" target occasionally, because the errant factors between the shooter and his equipment are multiplied by each other. I remember zeroing a scope recently, and fretting over the fine tuning, as the group got smaller, each shot had to be critiqued more minutely as to whether its location on the target was due to the shooter or the equipment. With a handgun, this effect is much greater. Closer range, larger diameter bullets, cruder sights, and the effectiveness of the shooter are more difficult to diagnose correctly. Even when all the fundamentals are there, a bullet might land an inch left of the point of aim at 25 yards, and its difficult to determine the reason. Most handun sights are not capable of being minutely adjusted to allow a great shooter of truly exploiting the mechanical accuracy, which then hiders the practical accuracy, as there is difficultly in determining the mechanical accuracy and its ergonomic relationship with the shooter. |
September 6, 2020, 04:36 PM | #30 |
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https://blog.forecast.it/hs-fs/hubfs...-precision.jpg
Accuracy vs. Precision: Precision is the size of the group without regard to the aim point, AKA Repeatability. Accuracy is (in simple terms) the |sum of the distance| of each shot from the aim point. They are different. MOA, when shooting at a target (like a deer), is the latter, not the former. (i.e.; Having all 5 shot hit within 0.1 inch from each other, but 100 yards from the deer is a worthless result and somewhat meaningless when the target ran away)
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September 6, 2020, 05:11 PM | #31 |
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MOA can be used to measure either the group size OR the distance of the point of impact from the point of aim.
MOA is simply a measure of angular distance and can be used to measure any angular distance desired, whether it's the distance between the two shots farthest apart in a group, the distance between the point of impact and the point of aim, or the angular distance between two stars in the night sky.
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September 6, 2020, 10:53 PM | #32 | |
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Quote:
I disagree that MOA refers to the latter. When we (at least, most shooters of my acquaintance) talk about a rifle that's capable of 1 MOA or 1/2 MOA, they are referring to the size of the groups that rifle will produce, not where the group falls relative to point-of-aim. If the rifle is capable of consistent groups (which is "precision"), accuracy is then a question of sight regulation ... and shooter. Neither of those affects the MOA precision of the firearm. Using your example of shooting at a deer: If you shoot at a deer with a sub-MOA rifle and miss -- that doesn't mean the rifle was suddenly not capable of sub-MOA "precision," it means you missed.
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September 7, 2020, 07:26 AM | #33 | |
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