Coping with the heartbeat artifact--how?

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  • Coping with the heartbeat artifact--how?

    When I shoot from the bench using magnified optics, trying to print the smallest groups I can manage, one of the things that constantly frustrates me is the slight scope reticle movement relative to the target with every beat of the old ticker--the heartbeat artifact. Despite my position on the gun and the positioning of sandbags or bipod, I can never eliminate the artifact. Consequently, my groups suffer. I've tried timing shots between heartbeats, but I find that usually causes me to jerk the trigger instead of pressing it, resulting in no improvement in group size.

    What technique(s) do you employ to minimize the heartbeat artifact in your shooting?

    Thanks,
    Scott

  • #2
    Scott,

    I've heard that certain Olympic shooters train on a heart monitor, that provides some type of usable feedback so the shooter can learn to shoot between the beats. I think the AMU might do it, but I'll have to confirm that.

    For practical techniques, I like to "go to sleep" on the gun with my body, while keeping my mind sharp. You can also dial back on your optic magnification if you have a variable scope. This is why certain benchrest shooters use rifle rests and don't really touch the gun much, other than slapping the trigger lightly.

    You also have the feedback of where your reticle is when the heart is in a cardio-pulmonary pause, although this is a fraction in time. The slower you get your heartbeat, the better off you are, so lay off the coffee, Mountain Dew, chocolate, etc.

    I like LR1955's simplified approach to this using the attentional focus of maintaining a good sight picture throughout the process of shooting. If you are able to fine-tune the break of your shot at the cardio-pulmonary pause, you're pretty talented.

    LRRPF52

    Comment

    • LR1955
      Super Moderator
      • Mar 2011
      • 3355

      #3
      Scott / F52:

      LRRPF52 is certainly on the right track. The end state is focusing attention on the right things at the right times.

      Look at attentional focus as an end state and the better you control the conditions, the more able you are to dedicate full attention to that one thing you must do for success.

      So, lets start out by controlling the conditions with the intent of developing a set of conditions that maximize your ability to focus.

      For Scott -- I have some training drills you can do to assist you but before I know what ones will give the highest probability of working -- got to ask a few questions.

      First -- what does 'smallest possible' (groups) mean in terms of inches and distance.

      Second -- are you holding your breath before you shoot?

      Third -- what pattern is your reticle holding on your target and how big is that pattern in inches and distance.

      Forth -- have you done anything to eliminate the effect of your pulse on the rifle? If so, what have you tried and how much did it work?

      LR1955

      Comment


      • #4
        Gents, thanks to you both for the replies. LR, I'll answer the questions you posed.

        1. Smallest possible group? From a bench, most of the groups I shoot hover around 1 to 1.5" at 100 yards (this with not only the heavy bbl Grendel but with a HB .223 and .308, too). I believe my HB Grendel with Les Baer tube should be consistently sub-MOA capable. Though I'd like to shoot 1/4" group after 1/4"group, I think a more realistic, consistent number is in the 3/4" range, with the occasional group into the .5" range. This at 100 or similar MOA at 200 because those are the only distances to which I have frequent access.

        2. Breathing pattern? Inhale deeply a few times to oxygenate my blood (but not to the point of lightheadedness), final full breath, exhale half breath and hold, squeeze trigger.

        3. Reticle pattern? From point of hold at 100 yds, the reticle jumps toward 2:00-ish approximately .5" to 1" with every heartbeat. However, after the beat, though the reticle settles, I find that it doesn't always settle exactly to my point of hold, perhaps another .25" of slop. Even if I do manage to time the break of the shot between heartbeats, I'm still dealing with anywhere from a quarter to half inch of uncertainty in shot placement at 100. Does that make sense?

        4. What have I done to eliminate the heartbeat artifact? Bagging the rear of the gun as solidly as possible minimizes but doesn't eliminate the artifact. Even letting the gun free recoil, contacting the gun with hand on pistol grip and cheek on stock only, shoulder not touching the buttpad, still doesn't eliminate the artifact. Shooting the gun in a field-type position, with the aid of a bipod only while supporting the butt or grip with my off hand/arm, significantly exacerbates the artifact.

        My intent is to try to test the mechanical limits of the gun as best I can so when I am in the field I know, in theory, what margin of error I need to accept with my aim. I don't feel like I'm quite there, yet. That last 1/4 MOA sure is elusive!

        Comment

        • LR1955
          Super Moderator
          • Mar 2011
          • 3355

          #5
          Originally posted by ss355 View Post
          Gents, thanks to you both for the replies. LR, I'll answer the questions you posed.

          1. Smallest possible group? From a bench, most of the groups I shoot hover around 1 to 1.5" at 100 yards (this with not only the heavy bbl Grendel but with a HB .223 and .308, too). I believe my HB Grendel with Les Baer tube should be consistently sub-MOA capable. Though I'd like to shoot 1/4" group after 1/4"group, I think a more realistic, consistent number is in the 3/4" range, with the occasional group into the .5" range. This at 100 or similar MOA at 200 because those are the only distances to which I have frequent access.

          2. Breathing pattern? Inhale deeply a few times to oxygenate my blood (but not to the point of lightheadedness), final full breath, exhale half breath and hold, squeeze trigger.

          3. Reticle pattern? From point of hold at 100 yds, the reticle jumps toward 2:00-ish approximately .5" to 1" with every heartbeat. However, after the beat, though the reticle settles, I find that it doesn't always settle exactly to my point of hold, perhaps another .25" of slop. Even if I do manage to time the break of the shot between heartbeats, I'm still dealing with anywhere from a quarter to half inch of uncertainty in shot placement at 100. Does that make sense?

          4. What have I done to eliminate the heartbeat artifact? Bagging the rear of the gun as solidly as possible minimizes but doesn't eliminate the artifact. Even letting the gun free recoil, contacting the gun with hand on pistol grip and cheek on stock only, shoulder not touching the buttpad, still doesn't eliminate the artifact. Shooting the gun in a field-type position, with the aid of a bipod only while supporting the butt or grip with my off hand/arm, significantly exacerbates the artifact.

          My intent is to try to test the mechanical limits of the gun as best I can so when I am in the field I know, in theory, what margin of error I need to accept with my aim. I don't feel like I'm quite there, yet. That last 1/4 MOA sure is elusive!
          Scott:

          Yes, you should be holding about 3 / 4 minute pretty consistently with a LB Grendel providing you are using ammunition that will give performance, have a trigger that will give the performance, a stock that is ergonomically and mechanically designed to allow for the performance, an optic that is not only very good but also adjusted properly, and an aiming point that is the right size and color for performance. If your Grendel and .308 are top end using top end components, and you shot ten each, five shot groups, and culled shots that were way out but did go to your call, - you can expect your mean to be a minute or slightly less with 1 SD being somewhere around 1/4 or 1/8 of a minute. A exceptional AR in .223 with the perfect loads will probably have a mean of .75 MOA with one SD being about 1/8 minute. Why? Lighter recoil.

          If you want to shoot groups that have a mean of 1/4 minute, buy a bench rest rifle chambered for a 6mm BR or PPC and get into the bench rest sport. You can shoot 1/4 minute groups with a gas blaster or a .308 but the few times it happens for five consecutive shots will be primarily due to chance.

          I think you also need to define some sort of way of measuring your performance both from a bench and from what ever position you will be using in the field. What you must decide on is how to identify and deal with outliers. In this case, you set your own conditions and standards. So, set your conditions and standards and if you want I am sure we can all offer advice.


          OK -- right now your attention is being taken from what you must do to get consistent performance and is being directed towards seeing the effects of your heart beating through your optic. Not a problem. Accept its movement. It is obvious you believe you have done everything possible and it remains to an extent so you have two choices. Either accept it or let it destroy your performance. Can you eliminate it completely? From a bench rest position you certainly can and that will take experimenting until you have found a position and method of control over the rifle that either totally mitigates the effect or eliminates it. A hard hold is a good start point but right now -- either accept it or let it ruin your performance.

          What most guys do when dealing with movement caused by heart beat is to shoot when the reticle is at its apex or bottom of its range of movement. Just note that we will adjust our position until the movement is mitigated as much as possible given the conditions we are shooting. We will depend on controlled breathing -- be it slow or fast -- as a means of getting our attention focused on what is happening with the sights -- shifting attention towards sight picture so we can see if we need to do other things in order to reduce movement or if our movement is just fine for the task. When your attention is focused outwards on the sight picture, you note the pattern of movement while you breath and see basically two things that tend to make guys believe they are in control. One is that the pattern of movement is very consistent and second that the speed of movement is slow enough that the shooter believes he is more than capable of getting shots off at the right place in the movement area. I prefer to break shots at the bottom of the range of movement but understand that I am controlling the rifle so if the movement doesn't stop at precisely the same place, I literally shift the rifle's point of aim by letting out more air from my lungs or relaxing my upper body a bit more or a combination of both (most likely).

          Let me suggest that you practice this technique of putting yourself back in control of your rifle so you can see how it works and perhaps gain some confidence that you are in control -- totally and without an iota of question.

          So, take out your .223 blaster, ensure it and your optic is mechanically sound, and get some proven ammo. Get your bench set up to fit you and give you a good point of aim. Use a black dot for an aiming point. Try a two inch black dot at 100. Adjust your magnification until the center of your cross hair or dot covers enough of the black so that 1/4 of the black can be seen around the center of your cross hair. The center of your cross hair or dot will cover a large amount of the black dot.

          Load five, get into position and breath while watching the cross hair and its movement. Yes, the center of your movement will be around the center of the dot. When you have let out the air in your lungs at a comfortable point for you, see where your heart beat is taking your cross hair. Most likely it is taking it in the same direction as your breathing. See where it stops and for how long. Most likely you will see it stopping at the low point for the longest amount of time so adjust your position so when you go into your respiratory pause, the dot or cross hair is pretty close to the center of your dot. Dry fire and adjust more as you see fit but do the process very quickly. When you see the cross hair center in your dot (after you have held your breath), fire the shot.

          Dry fire ten or fifteen times and develop your technique. Then go live.

          For live, fire a five shot string in fifteen or at most twenty seconds. Shouldn't be hard to do with a .223. Run a couple of strings like this and adjust your thinking and position as you see fit. Avoid looking at each bullet hole as it appears. Do not use a Shoot-N-See for this one as it will cause too much stimulus that will shift your attention. Just a plain black dot. Do not adjust your magnification so you see more than about 1/4 of the dot around the center of your cross hair. I want the cross hair to blot out about 3/4 of the dot to reduce stimulus. Also, if you shoot bullets into the center this time, you won't see the holes because your cross hair is covering them. Shoot quickly and confidently and do not look for holes until you have fired all five shots. After firing the five and before looking -- call each of your shots please. Then compare your group to your calls.

          Practice this with your .223. Reflect on action, adapt but maintain your focus on the process of shooting consistently well and not an outcome. If your process is perfect and the outcome isn't -- you need better equipment.

          LR1955

          Comment


          • #6
            Shooting at the ebb....

            We were always taught that, of course it was guys like you teaching it.

            This was not however taught at the big ARMY level.

            Comment


            • #7
              Holy smoke, LR! Thanks very much for the detailed explanantion. I'll reread your post a few times to make sure I understand clearly, then I'll try what you suggested and report with the results. Might be a while because I'm on vacation this week and don't plan to spend much time in front of the keyboard, but I will provide an after action report.

              Again, thanks so much for taking the time to pound all those keys!

              Scott

              Comment


              • #8
                I obviously agree with everything said prior, as it is quite sound and expounded by quite knowledgeable writers. I may have missed it, but I didn't see what you were doing with your left hand. I have the same problem, after three heart valve surgeries, and quite a forceful heartbeat with a very small chest. I found the last factor that helped me, of course shooting off a heavy concrete bench that doesn't move, is to take my left hand and brace it on the table, and pinch the ears of the rear bag, and this reduces reticle oval of movement down to 1/2 of what it was, which means a group 1/4 of what it was, or about 1/2 MOA for me. I certainly won't argue with those more knowledgeable if they have a better suggestion, but I do know in my case that it does work for me personally, if not for anyone else. I also use a 2 stage Geiselle trigger, because that is what I use to build most of my guns for myself and I am quite used to it.

                Comment


                • #9
                  You can also slow your heartbeat very rapidly for a few seconds with stimulating your vagal nerve. You bear down really hard like your taking a dump, holding your breath. Let go and breathe...Your pulse should slow. Takes some practice but don't try this if you're on any beta blockers or have a low heart rate. You don't want to pass out!!
                  Last edited by Guest; 06-23-2011, 10:26 PM.

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                  • #10
                    And you don't want to try it if you really need to go too.

                    Just kidding.

                    --fanofflyn

                    Comment


                    • #11
                      Like LRRPF52 said, "fall asleep on your rifle" my coaches sometimes had us actually try and fall asleep on our rifles just to know that thats how relaxed we should be.

                      Comment

                      • LR1955
                        Super Moderator
                        • Mar 2011
                        • 3355

                        #12
                        Originally posted by YutYut View Post
                        Like LRRPF52 said, "fall asleep on your rifle" my coaches sometimes had us actually try and fall asleep on our rifles just to know that thats how relaxed we should be.
                        YY:

                        Can someone ever be too relaxed to shoot well?

                        LR1955

                        Comment


                        • #13
                          physically i personally don't think so but mentally yes. (This is mainly speaking for the prone position) The mind has to stay fully awake. Kind of like when you first wake up in the morning but you're so comfortable your body doesn't move an inch, yet your mind is fully awake. . what i was taught was to sight in, close my eyes and relax. take deep long breaths for a few minutes then open my eyes slowly and i should be at my natural point of aim. if not, repeat the process until i find it.

                          Comment


                          • #14
                            I don't know your age but when you are relaxed in a quiet place you might try slowing your heart rate by using your breathing rythm. It's not so much your respiratory rate buy when you exhale in a relaxed but complete and extended way your atria fill more completely and your rate slows. As you gain control of your heart rate check your natural point of aim. Close your eyes as your rate slows then open and see where your crosshairs are. Shift your hips to side to side or front and back to make that reticle be where you want it when your eyes open. Sorry if I'm telling you something you already know. You'd be surprised how much difference this can make. (See Appleseed Project online)

                            Alex

                            Comment


                            • #15
                              try not to treat an analog problem with a digital solution. My heartbeat perturbs the point of aim cyclically. All I have to do is make sure my body position is right so that I'm on at some point in the cycle, any point. Then I just have to keep my trigger activation consistent across that curve. Don't try to beat the heartbeat, you can't. You have to work with it. I'm only able to pull off .3 MOA on a good day so I'm no BR shooter but holding sub-MOA isn't really hard.

                              Alex and others covered every other point.

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