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Not possible...or is it?

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  • Not possible...or is it?

    I was just reading an old gun rag article written by Craig Boddington titled "The Trouble With Long-Range Shooting". In this article Boddington makes this comment! Quote: "This Remington 7mm RSAUM actually grouped a tighter MOA at 300 yards than it did at 100 yards-serendipitous but true".

    I realize that as the distance increases so does the size of the minute of that angle. If all factors remain constant then the size of the group at 100 yards has to increase proportionately to the distance....it can't get smaller!

    Maybe on a given day the author shot a better group at 300 than he did at 100 but but to claim that the gun shoots tighter groups(MOA) when the distance is trippled is against my better judgement and the law of physics.....or am I missing something?

  • #2
    Yep I remember a little fat rookie cop touting the shotgun in his first rag story and screwing up half the facts. His name was Maas something.
    Now left only to be a turd in the forrest and the circle will be complete.Use me as I have used you

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    • #3
      I think it was Massaads a'boob. Most, but not all gun writers make my brain hurt. Seyfreid, Boddington, etc. are difficult for me to have any interest in. But thats just me I guess.
      "A strong body makes the mind strong. As to the species of exercises, I advise the gun. While this gives moderate exercise to the body, it gives boldness, enterprise, and independence to the mind."

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      • #4
        If you shot through two targets with the same group, the further out would be larger even assuming the first target did no damage to the bullet or its flight. There is another factor involved. If you happened to have a scope that was parrallax adjusted fora longer range, say 200/250yds, it is very possible to shoot two groups with the further one being smaller.

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        • #5
          It's a fairly common occurrence. I have seen the same size groups at 100 and 200 yds. I've seen 1/2" groups at 100 and 200 yds with my Sendero 25-06 from the same load on the same day. It's due to a phenomenon called eliptical swerve which is the pitching and yawing of a bullet early in in it's flight path.

          Bryan Litz posted this thread in LRH with a video to help visualize it.

          http://www.youtube.com/watch?v=KH9SC...embedded#at=81

          http://www.youtube.com/watch?v=KH9SC...embedded#at=81

          Here's an article on his website... he's got a few good ballistic articles.

          http://www.appliedballisticsllc.com/epswerve.html
          "You will never know how much it cost my generation to preserve your freedom. I hope you make good use of it."
          ~ John Quincy Adams

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          • #6
            [QUOTE=rbuck351;924515]If you shot through two targets with the same group, the further out would be larger even assuming the first target did no damage to the bullet or its flight. There is another factor involved. If you happened to have a scope that was parrallax adjusted fora longer range, say 200/250yds, it is very possible to shoot two groups with the further one being smaller.

            The picture of his rig shows it wearing a Kahles scope with no adjustable objective and this is before anybody put the parrallax adjustment opposite the windage adjustment. Most likely the parrallax is set closer to 100 than 300. He makes no mention of it in his claims. Since the article was covering the details involved in long range shooting I'm guessing that had he altered the parrallax he would have mentioned it....maybe not!

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            • #7
              I'm not sure my brain can wrap around this - perhaps I shouldn't even try.....
              When asked what state I live in I say "The State of Confusion", better known as IL....

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              • #8
                I don't know about 100 vs 300, because I haven't seen that. But my favorite 7 mag shoots roughly the same at 100 and 200, but only with boattails. Fred Huntington claimed it was because the boattails hadn't "settled down" at 100 or some such when I asked him about it, saying he saw the same thing with his Rockchucker using longer bullets until he upped the twist rate a bit. Long ago in a land far away. I'm open to other explanations, but it happened for me in that one instance.
                "Lay in the weeds and wait, and when you get your chance to say something, say something good."
                Merle Haggard

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                • #9
                  Anything less than 10 shot groups are an absolute joke and have less than zero relevance. Most gun rags will hold up a 3 shot group and say "see, clover leaf". What a pile. 3 shot groups are great for narrowing down approximate scope zero but tell you nothing of a rifles or loads accuracy. Do the same 10 shot group 5 times and I will listen to what somebody has to say about accuracy.

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                  • #10
                    Originally posted by Smokey View Post
                    I'm not sure my brain can wrap around this - perhaps I shouldn't even try.....
                    Probably the best way to describe it is that sometimes bullets will "wobble" a little (pitch and yaw) when they leave the muzzle, then eventually settle down or "go to sleep". Sometimes they go to sleep in 50 yds, sometimes maybe 300. With both of my Senderos I usually get better MOA groups @ 200 and 300 yds than @ 100 yds. Not necessarily better inch size groups but almost always better MOA. The best MOA range seems to be about 200-400 yds.
                    "You will never know how much it cost my generation to preserve your freedom. I hope you make good use of it."
                    ~ John Quincy Adams

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                    • #11
                      If the bullet leaves the muzzle at 1/2 degree of angle to get to 100yds at 1MOA, the bullets are not going to magically all turn toward the point of aim as apposed to any of the other 359 degrees they could all of a sudden turn toward. It could happen from time to time with three shot groups but certainly not on a regular basis. MOA could get better at longer range as the bullet "goes to sleep" becomes stable and quits wandering randomly but group size just won't get smaller farther out. Different manufactures have used different parrallax correct ranges over the years and I have no idea of the setting of the Kahles in question. And I agree that 3 shot groups don't say much. For those that have trouble getting this picture, take a ruler and paper and make two equal length lines touching on one end and an 1" apart on the other. Now about in the middle of the lines place two points an inch apart perpendicular to the centerline of the angle. Now put the ruler on the closed end of the angle and one of the mid point dots. This will show where the bullet is headed unless they all magically turn toward the center of the angle. Yes it is possible to shoot as small or even smaller groups at longer range but it's not sleepy bullets all turning toward the same point in space from the half way point on. As parrallax usually becomes less of a problem as you get further out, I suspect that has much to do with this.

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                      • #12
                        [QUOTE"This Remington 7mm RSAUM actually grouped a tighter MOA at 300 yards than it did at 100 yards-serendipitous but true".
                        ][/QUOTE]
                        So? The 100 yard group could have been 1", the 300 2 7/8". That fits the statement and is hardly shocking.

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                        • #13
                          Originally posted by rbuck351 View Post
                          If the bullet leaves the muzzle at 1/2 degree of angle to get to 100yds at 1MOA, the bullets are not going to magically all turn toward the point of aim as apposed to any of the other 359 degrees they could all of a sudden turn toward.
                          With eliptical swerve, the bullet is not leaving the muzzle at 1/2 degree off. It's "wobbling" along a fairly consistant flight path until it settles down. It's really nothing new and is observed and understood by most competitive shooters.
                          "You will never know how much it cost my generation to preserve your freedom. I hope you make good use of it."
                          ~ John Quincy Adams

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                          • #14
                            Originally posted by MontanaRifleman View Post
                            With eliptical swerve, the bullet is not leaving the muzzle at 1/2 degree off. It's "wobbling" along a fairly consistant flight path until it settles down. It's really nothing new and is observed and understood by most competitive shooters.
                            I think that's correct.

                            It's been observed, and there are plausible explanations for it.

                            As far as I'm concerned, "End of Story".

                            Smitty of the North
                            Walk Slow, and Drink a Lotta Water.
                            Has it ever occurred to you, that Nothing ever occurs to God? Adrien Rodgers.
                            You can't out-give God.

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                            • #15
                              Well, let me put it another way. If the bullet is deviating away from the group center, and it had to to get anywhere other than dead center, it is not going to change from its present flight path away from center back toward the center of the group unless acted upon by some force. The odds of all bullets shot to the left of group center turning back to the right and all bullets shot to the right turning back to the left is highly unlikely. The Idea of a rifle shooting 1" at 100 and 2 7/8" at 300 is easily within normal sizes for any two groups especially if large numbers of rounds are not fired.

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