TargetTalk

I would like to know peoples thoughts on how to minimise sideways movement in the prone position. The SCATT shows that i have 20mm vertical movement and 40mm horizontal movement live fire puts the groups into a horizontal type spread. I know in the past when i have been scoring consistently higher the horizontal and vertical movement on the SCATT have been pretty much the same in terms of mm of movement.

I have tried variations on the sling but this doesnt seem to resolve the issue i have also made a new pistol grip that fits the shape of my hand better still not much improvement. I guess that it will have to be one of the points of contact so this leaves the butt placement and the cheekpiece.

I did move the butt out to the right however the movement did not decrease this possibly puts more sideways pressure into the cheekpiece instead of downward pressure and doesnt resolve the problem either.

Your thoughts would be appreciated.

Hi Rob,

For prone, 20x40mm is a HUGE SCATT pattern, my friend. It would help a bit to know how long you have been shooting. This large a pattern is generally a result of inexperience in setting up the position - usually relating to overuse of muscle in the setup.

There are several sources that may be causing the movement:
1) Sling not tight enough
2) Sling positioned at the wrong spot on the upper arm
3) Sling not pulling from the outside of the arm
4) Head not relaxed on the cheekpiece resulting in too much tension in the neck
5) Inability to relax the right shoulder/arm/grip
6) Skewed geometry of the shoulders resulting in an unnatural strain

What we need to help you: Take some pictures from 10, 12, 2, 3, and 6 o'clock. Also include some from directly above the rifle and the right shoulder.

By looking at the position, we can eliminate the obvious and start working on getting you down inside 10mm. BartP

Just to add...

Once we get your position analyzed, we will start looking at your blinking rate, breathing process, your shot execution process, and relaxation techniques.

I use a noptel. When I bought it, my pattern was in the shape of an upside down T. 6mm up and 10-11mm wide. By changing my sling, handstop, and by getting my head relaxed, I was able to narrow down the elements and slowly arrive at a 6-7mm jiggle in the middle.

These things take time and a methodical mind. Be patient. all things are possible. :) BartP

Bart
I can't help but be drawn to your point 3 "Sling not pulling from the outside of the arm".
In many years of prone shooting I've always set up the sling in a straight line from the centre of the arm, have I always done it wrong? If so how do you stop it rotating to centre and then changing tension? or have I misunderstood your comment?
Robin

Hi Robin.

The sling keeper on your jacket is designed for two things. 1) To keep the sling from sliding down the arm and 2) (if your sling has a sling keeper notch or flange to attach it to) to keep the sling pulling from the outside of the arm. If the sling is coming straight out from the arm or there is undue tension on the inner/upper arm, your brachial artery will transmit a significant amount of pulse to your gun - thus disturbing your hold.

The MEC sling is designed to reduce this problem. It allows the shooter to adjust a secondary loop with a restrictor on it to handle the main strain of the sling pull. This nearly eliminates the pressure on the inner arm. Combine this function with FINDING the best place on your inner arm (the place that has the LEAST amount of pulse) and you can reduce the effect of the pulse dramatically. Look at your sling. Do you use the material of your sling keeper to maintain the height? OR can you add a 'hook' to your sling keeper so you can hook thru a hole or a metal flange?

You cannot help but improve your hold if you do this. The next issue may be with your hand stop. I recommend the smallest hand stop you can find. The pulse can also be transmitted thru your hand at the hand stop position. By reducing the size of the handstop you can pin your hand in using sling tension rather than allowing the space between your thumb and forefinger to shoulder all the weight, strain, and pain.

Let me know if you have any more questions. BartP

Thanks Bart for the reply I will get some photos posted as soon as i can. I have been shooting for the past 25 years in the early years i was pretty much on my own without a coach and may have some bad habits, I am sure i have taken some of them out by now, but there will be some left that i havent picked up. I have at times shot quite well with a different position to what i have now but the SCATT movement was still about 28mm for horizontal and the same for vertical. In saying that i did average in the low to mid 590's and top scored with 598 however i couldnt control the trigger very well and out of 60 shots 10 - 15 would go off when i wasnt ready not good for confidence.

Anyway i will get some pictures up.

Thanks Bart,
Very interesting, both my wife and I have always shot with a straight pull sling, ie a straight loop around the arm, we can adjust how tight the arm is held with an adjustable clamp but probably not easily the direction of pull, although I will experiment now. Yes we use a strap to hold the sling up the arm but will see if we can use it to adjust the direction of pull.
Yes, we both use virtually no handstop, or no handstop, and the hand is held by the sling as you suggest, this comes from us both having extensively shot full bore rifle and was done to avoid the recoil bruising the hand and now we just prefer it for smallbore, so its a bonus not transmitting the pulse from the hand.
Although I was not the original poster it has been most usefull, thank you.
Robin

I too was drawn to Bart's point #3...

As I like a high sling position on the upper arm and as my jacket is cut with an elasticated panel right where the sling crosses that Brachial Artery, I am quite familiar with this and have tried various methods to achieve a sling pull from the outside of the arm over the years.
However, in my case, while the pressure was reduced on the upper arm, the problems just moved elsewhere. My left shoulder felt like it was being pulled out of it's socket and I had pain under the shoulder blade.

Eventually I went to a self centering type sling and all is now well with relatively little pain anywhere - although my left arm does still go numb sometimes.

However, I'd absolutely agree with Bart's assessment that overuse of muscle is probably the source of the OP's problem, possibly coupled with being rolled over to the left too much/right shoulder too high/not enough weight on the right elbow.

Ken.

You are chasing a very elusive problem. When I came back to highpower 20 years ago after a layoff of 20 years, I saw that my movement was a constant 1/3 minute movement across the x-ring in a 10 to 4 direction. There was very little vertical or random movement and no obvious pulse beat. In the any sight matches where I could see my shots break, I could see that most of my shots broke in the middle (more of less) of the x-ring so I didn't spend a lot of time trying to track down the source of the movement. However, in 2001 I reached the shoot-off of the Wimbledon Match at Camp Perry and in the course of the shoot-off I saw to my dismay that the movement had flattened out so it was 9 to 3 and had increased to almost the whole x-ring. Again all but one of the shots broke in the middle and the one shot that broke at the very end of my movement at 9 o'clock came up exactly where it broke - a middle 10 at 9 o'clock. A bit of good fortune! I was keyed up during that experience and I have assumed that my heart rate was higher than normal so I reasoned that the movement was pulse related even though I didn't see any pulse beat. After that competition my hold went back to normal. BUT things have changed for the worse. My movement is still primarily horizontal but there are vertical excursions and it moves outside the x-ring. Bad news! Now I'm trying to manage my hold more carefully. I've noticed that the movement increases the longer I hold. So I take more care in appraoching the bull so that as I breath the front sight up on the bull it comes to rest in the center of the aperture. I try to get the shot off immediately. Maybe 1 to 2 seconds. If I don't get it off, I start over. I've tried different slings without any real improvement. I've also tried moving my left elbow closer to the rifle. I may may have seen a little bit of improvement with that. I have not tried any extra padding on the upper arm or a jacket with extra padding. I spoke with Lones Wigger briefly this past weekend at a local ARA benchrest match. He suggested a change of placement for my buttplate in my shoulder and lots more practice - live or dry firing. He guaranteed that I will improve. My own thought is that I not only would benefit from more practice but better conditioning. Those two are my resolutions that I hope will get me my Master Card. Mike Barron

Just to clarify, I think the OP's 20x40mm wasn't the size of the trace, but the length of it. Mine's about the same length (as reported by the SCATT), but generally stays within the 50m target's 10 ring.

Please have in mind that the "old" Scatt shows a different L-trace than the USB version. If you have an L-factor of 20-35 with the USB, it is not uncommon toe be 40-50with the old version of Scatt.

To Guest66
VCan you clarify your comment further? Not sure what you are referencing when you say "old version" and the USB in the same sentence. I have the USB Scatt and find it a challenge to get L-trace recordings into the 30's with any consistency even though the hold pattern looks really good.

I should clarify that it is the length of the trace i was talking about not the group size. I do use a USB SCATT and the group looks to be mostly in the 10 ring except for the pulsing which goes out to 10 oclock. I would assume that the areas that Bart mentioned above are still the areas to be looking at to minimise the movement.

Sorry for the confusion.

Any time I detect horizontal movement it has often been traced to improper NPA [zero hold] a small position change is the fix for me. Good Shooting Bill Horton

I have an self-centering sling (Jenson) that I use for prone. It will automatically pull from the center of my arm. I haven't found this to be a problem. Kneeling, however, I use a Thune sling so I can make it pull from the outside. My kneeling doesn't work at all with the self-centering sling, but prone does. Go figure...

Eric U

I should clarify something. I do not use SCAT - only noptel. The 'trace' I am referring to is the last 1.5 seconds before executing the trigger. The yellow portion of the overall trace movement. My YELLOW trace is routinely covered by the bullet icon once fired. That means that the yellow trace is around 5-7mm. I put emphasis on THIS trace as it is the last movement before executing the shot. The BLUE portion of the trace - the general movement leading up to the shot - is usually contained within the 10 ring (10mm). I'm not sure what benefit would come from the 'length' of the total movement during the execution process as it takes me a few moments to get things settled in to produce a center shot.

On Noptel, there is a measurement called COG (Center of Group - I think - never had a manual). THAT number takes an average of all the movement measured (during the final 8 seconds of aiming). THAT number is routinely 11-14mm and INCLUDES the entire trace (blue and yellow) to give you a good number to go after.

So...getting back to the original thread - I'd like to know the actual 'size' of your movement by measuring the diameter of your execution trace and the SHAPE of the movement - as if you had a ruler/architect's stencil to measure a shot group on a target. That will help narrow down the issues and get me on the same sheet of paper with you.

BartP

Bart, you're holding the bull for THAT LONG before releasing the shot???

Why?
What improvement in aim/sight picture are you getting after 2-3 seconds?

Personally, my NOPTEL/ SCATT traces would typically be mostly entering the bull from 6 o clock - 2 seconds settling in the X ring - shot.

8 seconds staring down the sights and you're basically guessing what the sight picture is. That's my experience anyhow.

Regards,
Ken.

Anonymous wrote:To Guest66
VCan you clarify your comment further? Not sure what you are referencing when you say "old version" and the USB in the same sentence. I have the USB Scatt and find it a challenge to get L-trace recordings into the 30's with any consistency even though the hold pattern looks really good.

Before the USB version was released, the first/older Scatt system used the serial port (or similar), not the USB.
Those two versions sometimes have som differences in how they display the L-trace.
Now, I wrote "L-factor of 20-35 with the USB, it is not uncommon to be 40-50 with the old version of Scatt". It could be the other way around, it was some time ago when I used the Scatt...

Hi Ken.

My shot process has several steps. The blue trace starts far ahead of actual aiming. I settle in on top of the bull. I am deep breathing, then blinking to ensure clarity, listening for my pulse in my ears, holding, timing the shot with the pulse, and executing. My best hold and sight picture arrive around 5-6 seconds into the actual aiming moment (once the breath is being held). But the rest of that stuff takes much MORE than 8 seconds. 2-3 seconds is FAST, bro. That's Warren Potent Fast. I have to take a little extra time because I have an oxygen issue. I have to take at least 6-8 deep breaths between each shot to ensure adequate vision and clarity THEN begin the execution process.

BartP

I think my vision actually begins to provide a clear sight picture because there is a slight delay from when the breaths are taken in to the time when the oxygen is showing it's benefit. I mentioned that I have a specific oxygen uptake issue - and it is severe. I can take in all the breaths in the world and it takes a great deal of time of that air to do it's work.

The only reason i mentioned the 8 seconds, is because THAT is the time interval that the Noptel uses. BartP