Here is a 20 shot group

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James
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Here is a 20 shot group

Post by James »

This time I was really focused. This target was shot after shooting about 40-50 shots.
Image
The first couple and last couple shots are the fliers.

This time I shot my pistol is canted to the left slighly, and the sights seemed really still. Just lift up and pop. Another thing I noticed was I physically pulled the trigger on each shot, None of them were subconsiously released.

Sometimes when i'm shooting my pistol is canted to the left slighly, as my arm wears out, I seem to straighten up as I struggle to hold the gun up.

My best match so far is 490, I seem to loose focus during a match.

My most recent match I shot a 485. But during the mock finals, I shot 90.something I seemed much more focused when you get only 75 shots per target.

Been shooting for about 4 months, and I am 16. I will be 17 next year so I will shoot in the J2 catagory still, if I shoot above 530 (qualifying score for nationals) but I turn 18 before the National compeition, and I move to the next catagory...am I still qualified? I'm not sure when the National competition is but I may be 18 before it.

Thanks, and any other tips?
Ernie Rodriguez
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Target

Post by Ernie Rodriguez »

Hey James-That target is OUTSTANDING dude.Congrats.Ernie
David Levene
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Re: Here is a 20 shot group

Post by David Levene »

James wrote:Thanks, and any other tips?
Very nice shooting.

One tip, if this happened in a match then don't be afraid to adjust your sights. A little bit down and left would have given a good return for the effort. Don't start worrying about why the group may have moved up and right. It has, so adjust to suit.

The fewer shots per target being shot in a match, the harder it is to spot that the sights are slightly out. It's much easier to spot on electronics, they tell you how far off centre you are.
Benjamin
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Don't adjust the sights!

Post by Benjamin »

The main part is contained with, and nearly fills, the 9 ring, and crosses the 10 ring. As long as a group spans the 10, you can't get much better by moving it. The only way to improve is to reduce the group size until it no longer includes the center of the target, then move the sights to center the group. Until then, one cannot judge where the shots are hitting, that ought to be 10s.

This is a good group. However, it is typical of what this shooter will be doing next year, not typical of the rest of this shooting session. Without seeing the other groups, which are presumably larger and solidly surround the 10 ring, it is not possible to judge whether sight adjustment would help - but I strongly doubt it.

- Benjamin
David Levene
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Re: Don't adjust the sights!

Post by David Levene »

Benjamin wrote:As long as a group spans the 10, you can't get much better by moving it.
I cannot agree. Looking at this target as an example, moving the sights down by approximately half a ring would have been beneficial. OK 3-4 points may have been lost by shots dropping off the bottom of their rings but, looking at that large hole above the 10 ring it is a fair bet that 6-7 points would have been gained.

An extra 3 points for a couple of clicks, that seems like a good return on effort.

Of course it would take a few shots to recognise that the group was forming high but, as I said, if you spot it happening then adjust. You have paid a lot of money for those fine adjustment sights, use them to give you a better score.
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Post by RobStubbs »

I've got to agree with David. The group should be centered in the middle of the target and this isn't. It is still a nice group and the shooter may have reasons behind the group pattern. However it is important to get used to moving the sights throughout a shoot and not just leaving them where they are. Far too many shooters set their sights up and then leave them (I notice it on my club range).

Rob.
James
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Post by James »

My coach makes a big deal about moving sights and stuff.

He says if its only one shot that you know should have gone in, try checking your NPA and adjusting your feet. If its about 3, grouping closely, move your sights.

In this case, I was practicing, and shooting to see how consistant I was (20 shots on one target) its more difficult to get afeel of how your pellets are grouping if your moving your sights constantly.

I remember reading about cutting out the 9 ring, and shooting, so you arn't concerned with the 10's and 9's but only the bad shots.

Is this a good idea? After shooting a 10, I sometimes rush the next shot, and dont follow proper procedure.
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Post by David Levene »

James wrote:He says if its only one shot that you know should have gone in, try checking your NPA and adjusting your feet. If its about 3, grouping closely, move your sights.
The number of shots before adjusting varies from one shooter to another. Your coach obviously knows you a lot better than we do. Listen to him.
James wrote:In this case, I was practicing, and shooting to see how consistant I was (20 shots on one target) its more difficult to get afeel of how your pellets are grouping if your moving your sights constantly.
Perfectly sensible. That's why my original comments on sight adjustment started with "if this happened in a match".
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Nicole Hamilton
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Post by Nicole Hamilton »

RobStubbs wrote:However it is important to get used to moving the sights throughout a shoot and not just leaving them where they are. Far too many shooters set their sights up and then leave them (I notice it on my club range).
As an engineer, this doesn't make a lot of sense to me. It sounds like the problem of trying to generalize from too small a sample size.

Let us imagine a given shooter were to run off a large number, say, several thousand shots. We would expect a distribution of some sort with a central area of greatest density and fewer numbers of shots as you move further away from that central area, representing the probability distribution. In adjusting the sights, the idea is to move that whole distribution around on the paper so that the expected value of any randomly-chosen shot is maximized.

But adjusting your sights based just on a small number of shots is like falling into the logical fallacy that if you flip a fair coin a few times and it comes up heads every time, then that means the odds of tails the next time have just gone up. They don't; it's still 50:50. What you don't know, just looking at a very small number of shots, is whether those shots were in the middle or the outlying areas of your distribution. And the only way you will know is by collecting a large number of shots.

Yes, of course, it does matter what your confidence is that you were correctly calling the shot. If you're damn sure you were on the 10-ring and had a nice follow-through on several successive shots but they all landed in a small group in 6-ring, then sure, that might be compelling that something is way off. (This is the idea behind sighters, e.g., to check your correction for a crosswind or distance in an outdoor high power rifle match or when first setting up a new gun.)

But what if your usual aim and follow-through and ability to call your shots isn't that good or that consistent? Should you adjust your sights for the highest score on just your best shots, the ones you were most sure you could call correctly? Not if your objective is the highest expected score, not just the highest score on your best shots!
James
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Post by James »

Adjust your sights so that when you have a perfect shot process, it lands on a 10.

If it misses due to you, thats your fault, and the sights should stay as is.

If your ability to call shots is bad, shoot more shots before you adjust the sights. but 3 shots closely grouping is i think enough to warrent movement of sights

But what if say you were thumbing the gun, and all 3, or even 6 shots land near the edge at 2 oclock. What do you do?if you adjust to move that to center, but then your thumb fatigues, and your hand pressure is as it should be then your shots are way off again......Its like poker LOL you can decide what cards you exchange, but what the other people have you can't control...or in this case, more difficult to control

But what if say I have 2 groups, both on either side of the 10. What do I do?

Can someone with good experience, describe their routine for adjusting sights in different situations during a match?
Steve Swartz

Post by Steve Swartz »

If, during sighters, my MPI is shifted from center ten I go back and diagnose my execution of fundamentl behaviors.

Then I tap my sight adjustment screws lightly with a screwdriver just to "put the mojo back in" or "exorcise the evil spirits."

At 10 meters, indoors, under fairly standard lighting conditions, using familiar ammo, and assuming you haven't dropped or otherwise abused your sights . . . what would cause the MPI to shift?

You, not the gun, are doing something different.

Steve Swartz

(But I always have a screwdriver at the bench and will occasionaly adjust the sights one click or so in an apparently random manner just 'cause.)
James
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Post by James »

What is MPI?

The gun should never change from where you last set it, if it does then something is wrong.
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RobStubbs
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Post by RobStubbs »

MPI - is I think 'Mean Point of Impact'

Your point of aim may well change throughout a shoot and to ignore it is asking for inferior results. Standing for 60 shots your body tires, your muscles fatigue and your eyes strain. And of course lighting conditions may be different from your home range.

Your sights are there for a reason and if you shoot a technically perfect shot that doesn't end up being that on the target then you need to rectify whatever the problem is. Now sure it may take you a few shots to be sure that it is a true phenomenon but once you have enough information to confirm that then you need to correct. Perhaps as Steve says you can re position yourself and see if that corrects things. However you need to be aware that it may well require a tweak of the sights. Heck 1 click is nothing very much and you can always click back again.

Remember in a match you are trying to maximise your score. You are not there to perfect your technique (that's what your training is for). So if a technical error ocurrs that means shots are going slightly off then I would suggest you change the sights now and adress the technical concerns when you get to your home range.

As a personal comment I will twiddle my sights maybe half a dozen times in a match. Mostly in the sighters but it's not uncommon to carry on and change them throughout the match.

Rob.
Dan

Post by Dan »

Steve,

are you really sure that the gun cannot possibly change the hitting spot through out a serires of 60 shots? I have always some vertical movement (never horizontal) and i used to think that this may be due to temperature changes (gun comes from cold cellar) in the cylinder. Its a Steyr LP10 btw....actually i had the same effect with my Hammerli, but that was precompressed too and also stayed in the safe downstairs over the week.

Does the aim/hitting area change due to temperature changes?

Anyhow due to this, when i start, usually i hit one or two rings too high...so during sighters i adjust sights. Over the series the hits get lower, until they are below the 10, at which point i adjust them back again (to the position they will be when i get the gun next time).

Does that make any sense?
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Nicole Hamilton
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Post by Nicole Hamilton »

RobStubbs wrote:Your point of aim may well change throughout a shoot and to ignore it is asking for inferior results. ... Your sights are there for a reason and if you shoot a technically perfect shot that doesn't end up being that on the target then you need to rectify whatever the problem is.
Sorry, Rob, the math doesn't support you, and neither does your argument about the technically perfect shot.

You should adjust your sights only when the probability is greater than 50% that doing so will improve your score, meaning you have statistically significant data suggesting that if you moved your probabilistic distribution of shots, that it would be better centered. To know whether you're over that 50% threshold requires, even if you do it by eyeballing it, that you consider (a) the sample size, (b) the distance by which the sample is off, (c) the shape of distribution from which the sample is taken and (d) your confidence that you actually know the distribution.

By way of illustration, consider two shooters of vastly different skill levels and a third of unknown skill. Shooter A is a robot who always puts every round through the same ragged hole. Shooter B is completely unskilled and produces a wide bell-shaped distribution with a standard deviation that's several feet across at the target distance. Shooter C is of unknown skill. Now suppose each shooter fires one round and each hits the 6-ring at 2 o'clock. What should you do?

The answer is that you're only justified in adjusting the sights for shooter A. For shooter B, the distribution is known but a sample size of one shot and an error of only a few rings is too small to be meaningful. For shooter C, you don't know the distribution to know if the sample is meaningful.

In real life, most shooters are neither robots nor blind men and they have some history to tell us about their usual performance. If the shooter is very skilled with a lot of history to tell us he always produces a very tight group, it may not take many shots or, alternately, for them to be very far off to be able to say with confidence that the sights are off. But with a novice shooter, it takes a larger sample and/or a larger discrepancy.

Given just a single target, e.g., the one posted at the beginning of this thread, I don't think that's enough data to tell you if the sights should be adjusted. Who's to say that even with no adjustment of the sights, that the next target won't just happen to be the mirror image, off by the same amount but in the opposite direction? The only way to know would be if we had more targets telling us that this shooter always produces very tight groups (confirming that a small error in a small sample is meaningful) or that even if it was a fluke that this group was so tight, it is nonetheless part of a pattern showing the distribution is off-center.

Regarding the "technically perfect shot," we need to return to question of what the objective is in adjusting the sights.

If the objective is to have all "technically perfect shots" in the 10-ring even if only the occasional shot is technically perfect and all the rest display have the same flaw, e.g., a consistent error in the sight picture, then sure, be my guest, adjust your sights for those occasional shots.

But if the objective is to maximize score, then it's not about where the technically perfect shots end up on the paper, it's about what happens to the overall distribution of shots, regardless of what skill or lack thereof is displayed in any given shot.
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Post by David Levene »

Nicole Hamilton wrote:Given just a single target, e.g., the one posted at the beginning of this thread, I don't think that's enough data to tell you if the sights should be adjusted.
Are you suggesting that you would carry on shooting a match, having shot those 20 shots, without adjusting your sights.

For some reason, and I don't care what it is, the group is forming higher than it should. A match is not the time to worry about what, if anything, is going wrong. A match is the time to get the highest score you can. Whatever is making the shots go high is doing it pretty consistently. Adjust the sights and take the extra points.
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Nicole Hamilton
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Post by Nicole Hamilton »

David Levene wrote:Are you suggesting that you would carry on shooting a match, having shot those 20 shots, without adjusting your sights.
Without more data, yes, I would leave the sights alone.

The additional data could come either from the shooter's history telling us that his groups are consistently tight enough that this tiny discrepancy is significant or from additional targets (shot either before or during the match) showing the same consistent misplacement. But without more data, you should probably do nothing -- except try to collect more data.
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RobStubbs
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Post by RobStubbs »

Nicole Hamilton wrote:
David Levene wrote:Are you suggesting that you would carry on shooting a match, having shot those 20 shots, without adjusting your sights.
Without more data, yes, I would leave the sights alone.

The additional data could come either from the shooter's history telling us that his groups are consistently tight enough that this tiny discrepancy is significant or from additional targets (shot either before or during the match) showing the same consistent misplacement. But without more data, you should probably do nothing -- except try to collect more data.
Nicole,
Your suggestions may be correct form a purely mathematical / statistical perspective but shooting is neither. You will not get a statistically meaningful dataset from a series of shots the population is just too small. So bin the maths and the statistics and look at the empirical evidence. If you are shooting a group that is not centered then you ignore it at your peril. It is telling you something is not right.

You will also know that you don't always shoot the same from day to day. The human body varies throughout the day never mind from day to day and that will contribute to where your shots end up on the card.

However that is all not really relevant. What is is that you want to maximise your score any way you can. If your group is not centered then you are not doing that.

Rob.
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Richard H
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Post by Richard H »

Being a former Quality/Reliability Engineer, the problem with Nicoles theory is that it assumes a stable system. Pistol shooting is not stable so you do not get a Guassian distribution. The process of a shot has many variables that can be slightly different on each shot, muscle fatigue, tension, stance, vision, balance, weight distribution to just name a few. So adjusting the sights is just a response to one of the other varibles changing to maintain an equalibrium. It is not tampering as Demming suggested as he was talking about a stable system when he talks about over adjustment.
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Richard H
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Post by Richard H »

I must say I do enjoy Nicoles posts, they are very thought provoking. Much better than the " what is the best pellet for my xxxx" or " what is the Best Air Pistol". I understand you might be going on the Germany Trip Nicole, I'm planning on it and it would be a pleasure to meet you.
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