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One of Us |
Curious. You have a rifle without a cheek piece that that you are shooting with iron sights and the iron sights have the point of impact centered. The rifle is being shot right handed. If you add a removable buttstock cheek piece on the left side of the butt stock, what direction will the point of impact move? I understand that you move the rear sight in the direction that you want to move the point of impact, e.g., moving the rear sight to the right in my example without a cheek piece will move the point of impact to the right. I get the dynamic when you are talking about the interplay of the front and rear sight . . . but adding in the dynamic of changing the cheek position leaves me baffled. Mike | ||
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| One of Us |
Interesting question. I suspect if your sight picture is the same that your cheek and eye position will change and there will be no change in point of impact. On a shotgun the eye functions as the rear sight as well as pointing instead of precise aiming and will change point of impact. if you actually forced yourself to aim a shotgun by lining up the front bead with the midpoint of the receiver, then I imagine the point of impact would be the same. | |||
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Adding or subtracting a cheek piece has no baring on the POI, only the sights and your eyes do, nothing changes that..you can lower the comb or lift the comb and the POI remains the same, cast off, cheek pieces change nothing other that if the stock no longer fits you, you may have to cuddle up to it get a proper sight picture. Ray Atkinson Atkinson Hunting Adventures 10 Ward Lane, Filer, Idaho, 83328 208-731-4120 rayatkinsonhunting@gmail.com | |||
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But your eye position is changing . . . by virtue of the cheek piece moving your cheek to the left, your right eye is being moved to the left as well is it not. Mike | |||
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Remember grasshopper,the sight picture never lies! Who said that? I think that was shootaway. | |||
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If you line up the sights after adding the cheekpiece, you are just squeezing your face tighter to the comb. I don't think you are changing the actual position of the eye. If you put a real thick cheekpiece on, the you wouldn't be able to line up the sights. | |||
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For your sights to line up your eye has to still be inline. As was thirdbite stated you will be forcing your eye over to line up. POI shouldn't change. As usual just my $.02 Paul K | |||
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There is no parallax using iron sights simply because line of sight is determined not by the position of the eye or head but by the line of sight between the fore and rear sight. If it were a scope the scenario would be very different because there position of the eye would have an effect. | |||
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Thanks for the feedback, I think I got it. Mike | |||
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+1. It would be the same as shooting a scoped rifle that is parallax free as ALF stated. There is no conflict between any image plane to cause an error. If your eye can line up the rear and front sight, then put the front sight on the target it doesn't matter where your cheek is. E | |||
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| One of Us |
correct sight picture is correct sight picture. Now if you add a cheek piece and your sight picture is slightly less aligned, then your impact will change but that is only because you altered your sight picture. Now, if you decide not to align your eye perfect with the sight picture after you add a comb, then your eye should be more to the left causing you to shoot more to the left just the same as if yur adjusted the rear sight left, it would cause your impact to move left. | |||
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Respectfully disagree or rather say partially agree Sight picture is the position of the front relative to the target. ie where on the target you position to foresight and how full or fine you align the front relative to the rear. by necessity a open sight forces the eye to be aligned with the line of sight between fore and aft if your eye is not aligned you cannot align fore to rear. A peep or ghost ring sight however is a different animal because here there is possibility of parallax that is why head position on stock in competitive shooting using aperture sight is important. | |||
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Right. A shotgun with only a largely ignored front bead and an eyeball for sighting is a different beast, where cheek position will greatly affect POI, versus a rifle with front and rear open sights plus an eyeball where all are forced to align regardless of cheek position, and no effect on POI, and no parallax. Interesting about the aperture/peep rear sight and parallax, good to know. I never though about that, never having been a "serious" target shooter. There, the front sight is very much not ignored, but the rear aperture is partially ignored, and foolery with the cheek position can cause parallax errors there, I do see, pun intended. Thanks Alf. RIP | |||
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I'm sure that those who have more experience than I will chime in, but doesn't "how" you hold the rifle have some effect on point of impact? You can have the exact same sight picture, but use a sling for a brace and you may change the point of impact. Use a sling attached to the barrel band and it will be "another" different. Put the rifle on a rest and it will be "another" different. Put the rifle on sticks and how you hold the sticks/rifle will be "another" different. I think the dynamics of the interaction on how the rifle is held does have a difference, meaning that a cheek piece may alter that dynamic, because it could change how you hold the rifle. OK, I'm ready to hear that I've got it all wrong. (and what's true for handguns may have no bearing on what's true true for rifles). _________________________________ AR, where the hopeless, hysterical hypochondriacs of history become the nattering nabobs of negativisim. | |||
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Mike, I think the POI will move, for the irons, if you add a cheek piece -- you could blue painters tape a doubled up neoprene mouse pad to the stock and see ... i think it'll move more than a little opinions vary band of bubbas and STC hunting Club Information on Ammoguide about the416AR, 458AR, 470AR, 500AR What is an AR round? Case Drawings 416-458-470AR and 500AR. 476AR, http://www.weaponsmith.com | |||
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The principal action in shooting with a rifle is the eye seeing the target. This is a principle of vision ! if we point a finger at the target it is us bring our finger up to our line of sight not the other way around. Though intuitively we think of it as bringing our head to the rifle it's actually the other way around as the rifle and sights has no ability to see or align itself to the target. There is a line of sight between the eye and the target. The rifle then actually gets brought up to this line of sight so that the sights align with the target. If you change stock configuration the sights still have to be brought into this eye to target alignment, which would means its the rifle position relative to the head position that has changed, not head to rifle. ( i know it sounds weird but that is how it is.) The trick of precision shooting is to have a comfortable body position and then to fit the rifle/ stock to line up with the comfortable position. Choosing a shotgun or a rifle is often done this way. You stand looking at the target in a natural comfortable shooting position, then close your eyes bringing the gun up, aligning it to where you think it should be then open your eyes and you see how well the gun is aligned relative to your line of sight. If its well designed it will line up, if poor you would need to adjust. Even if we are on a bench we have to bring the rifle in alignment to what we see. On adjustable rests we adjust the rifle position so that the fore to aft alignment lines up with our line of sight. | |||
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Interesting question Mike. I'm curious to see someone try it and shoot it over a long distance (~600 yards) to see if it magnifies a small variation into a noticeable difference. I shoot primarily left handed but practice a lot right handed (right eye) to maintain proficiency. At 1,000 yards my 6.5x284 match gun will shift its groups 6 - 8 inches to the right. I don't notice any difference in sight picture but my eye position is obviously different. When I tried a right handed shooter's Blaser my groups were over 20" left at 1,000 yards. Frank "I don't know what there is about buffalo that frightens me so.....He looks like he hates you personally. He looks like you owe him money." - Robert Ruark, Horn of the Hunter, 1953 NRA Life, SAF Life, CRPA Life, DRSS lite | |||
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Not sure what they teach with plastic and aluminum rifles, but when I was taught with an M14 we were taught sight alignment and sight picture, body alignment and "spot weld". What you are talking about with the cheekpiece would relate to spot weld. the spot weld position, that is the position on the stock where the shooter placed his/her cheek/mouth and generally the knuckle of their thumb was noted so that it could be repeated for several firings. The sight picture and sight alignment were paramount to the shot, but the body alignment and spot weld were primary contributors to the repeatability of on target shots. So while the changing of your cheekpiece may not directly change your sight alignment and sight picture, if it causes you to use muscles to keep them, your group size will increase. | |||
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Truth Spoken Ray B. Also just the force the Body effects on the rifle will move the impact of the shot no matter the sight picture. Just lay a rifle in a pillow, align the sights, pull the trigger with a string. Repeat. Do same in a rifle vise. POI is going to move. Yes I know it is extreme examples but explains why pretty well I hope. "The liberty enjoyed by the people of these states of worshiping Almighty God agreeably to their conscience, is not only among the choicest of their blessings, but also of their rights." ~George Washington - 1789 | |||
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Of course any major change to the rifle like adding a cheekpiece with weight and balance change or contact point pressure change when the rifle is brought to bear ... Of course you are going to have a POI change and you are going to need to re-zero your sight. But that is an immensely complicated change, hard to predict, that might amount to very little, or a lot, and it is just taken care of by re-zeroing to the new state and then being consistent to the new state. The OP seemed applicable to sight adjustment only relative to a new eye position, which as we see is a moot point. Just do it, shoot it and see how you need to adjust. You will get no simple answer or rule of thumb here, no lazy way out of this one.  | |||
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Lots of folks are overthinking this thread..I know the cheek piece or the position of the head makes no difference, Ive shot irons as much or more than anyone I know, grew up shooting them long range in the rimrock mountains of the texas big bend.. But, I have a couple of old leather cheek pieces and a couple of wood ones, so I'll give it a try..but Im betting dollars to donuts it won't make one iota of difference.. Ray Atkinson Atkinson Hunting Adventures 10 Ward Lane, Filer, Idaho, 83328 208-731-4120 rayatkinsonhunting@gmail.com | |||
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Not that I want to give the old bastard any credit---( Ray  ) but I have 2 stocks made by Ray Atkinson--work great with both irons and scopes- now they are both on 416's so I have low power scopes and low rings on them--pretty straight with english cheek pieces. "The rule is perfect: in all matters of opinion our adversaries are insane." Mark Twain TANSTAAFL www.savannagems.com A unique way to own a piece of Africa. DSC Life NRA Life | |||
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I think the OP was suggesting that moving the cheek because of an added cheekpiece would move the POI in a predictable manner like moving the rear sight. I still don't think that is correct assuming the eye, rear sight and front sight are still aligned. Changes in how a rifle is held can and likely will change POI; however, I don't think it is predictable. | |||
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If a stock doesn't fit you, its logical that you misalign it on a quick shot..If your sight picture is correct and aligned properly that is where a sighted in rifle will hit, end of story... The human body btw can quickly adjust to any stock if you put your mind to just shooting it..I have shot many iron sighted rifle milsurps and custom rifles that didn't fit me worth a damn, but if I continued to shoot them a bit the ended up working..Anyone can do this and a whole bunch of folks that don't know better get away with it all the time..If one thinks ever factory fits all shooters, guess again, but apparently they sure get er done..... Ray Atkinson Atkinson Hunting Adventures 10 Ward Lane, Filer, Idaho, 83328 208-731-4120 rayatkinsonhunting@gmail.com | |||
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I respect the opinion of shooters far more experienced than me. This thread got me thinking though.. Over the weekend I visited with a friend that badly wanted to shoot my 577. So we set up and started banging away. 3" black spot, roughly 30 yards off hand. All shots slightly right.... I normally kill a bull at that range. Knowing it's not the rifle, it's rarely the equipment... I didn't want to adjust the sights as I've never touched it since it got back from Westley Richards and thorough going over. I've added a new leather ammo carrier/pouch on the butt stock. The leather is 2mm or so thick. Haven't shot it since. Could it possibly be this??? My three shots were all the same, perfect elevation just right of the bull. My friends were right and a bit high. Both right handed shooters. He's final shot hit the bull by compensation a touch left. I can't come up with a plausible answer... I've used this rifle for what must 10 years now. What's gives?? | |||
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WoWo, No, nothing has changed, what happens is POI can move based on sunlight, if the sun is on the right side of the rifle, it give you a false picture and your shots will be to the right or left, can't remember which, the the same on the other side..If you zero in the evening or in shade always figure out how the gun shoots in sunlight..but this has nothing to do with alignment of your eye to the sights, you just got cheated by mother nature.. Wait until its nice and warm outside then shot a 4 shot group every couple of hours during the day and see how much the POI moves, fortunately you will probably remain in a 6 or 7 inch group average..Very few folks ever learn their iron sights, most don't even know the movement and they still bring home the bacon each year. Ray Atkinson Atkinson Hunting Adventures 10 Ward Lane, Filer, Idaho, 83328 208-731-4120 rayatkinsonhunting@gmail.com | |||
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Ray Atkinson Atkinson Hunting Adventures 10 Ward Lane, Filer, Idaho, 83328 208-731-4120 rayatkinsonhunting@gmail.com | |||
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| one of us |
I have certainly seen what Ray is talking about, shockingly, in my own shooting with open sights and a bead front sight. In fact, I do not think Ray was the original discoverer and reporter of this phenomenon. That probably happened back in the late 1400's, i.e., toward the end of the 15th century, when Ray was also co-inventing straight grooved rifling in Austria, soon progressing to putting some twist on it, perfected no later than 1520 in Germany, probably earlier.  Example: When the front sight bead is brightly lit from sun more on left side of bead, and right side of bead is in relative shadow, shooter will see the bead as being more prominent on the left side, so the bead seems to be located more to the left than where it actually is. Non-superhuman human vision being of limited resolution creates this optical illusion and mental perception. So the shooter compensates by moving the bead slightly to the right in its resting place in the rear sight. That will make the gun shoot to the right, even though perfectly zeroed for a neutral lighting. This happens with either open/V or aperture/peep rear sight Same for a blade/post as a bead front sight. Optical illusion. Riflecrank Internationale Permanente  | |||
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| One of Us |
Many old fundamentals and fine points of iron sight usage have been lost in the mists of time. Things that shooters just knew; although they may or may not have understood the reasons. They just knew. Experienced shooters knew that "bullets shot away from the light." They often didn't know why; just that they did and that blackening the sights minimized the effect. Bright brass beads made it worse. Here's another; usually spoken by an old timer deep in his cups, and in a lowered voice after a furtive glance around to see if anyone else was listening. "Bullets hit higher at night". I especially like that one when it's followed up with "never knew why, but they do".  | |||
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your spot on excepts bullets don't hit high at night or evenings, the shooter takes a courser bead, as the light is bad..Same applies early in the morning at day break..Ive been shooting irons my whole life and mostly in high rimrock country where shots are long as a rule..You figure all this out in time, sometimes it works, but don't bet money on it!! Ive seen lots of deer killed at 300 or more yards with iron sights as that's all we had back then or rather none locally believed in scopes.. The best shots with iron sights actually used the 30-30 carbine, or maybe a 300 Savage if they were flush..If they missed they shot over not under as you would suspect, they knew just how much sight to take in the buckhorn to hit as 200 or 300 yards, and aimed low at 100 to dead on at 150..They had been shooting the same gun since birth I suspect and they could damn sure shoot, and mostly military trained for WW1 or WW2 maybe.. They were also in the minority. Most of the ranching community just waited until a deer was about 50 to 100 yards and probably out the PU window, while doing daily checks on cattle or whatever. I also remember when every adult male in the family got a new .270 Win. and the boys got the then new .222 reml model 722...Bill Weaver and Jack O'Connor had hunted with us that year for the second time I think, and for Christmas we all got 2.5X Weaver scopes..Once we figured out the sighting in thingie, they worked great, and the trend was set....That's a funny story in itself.. Ray Atkinson Atkinson Hunting Adventures 10 Ward Lane, Filer, Idaho, 83328 208-731-4120 rayatkinsonhunting@gmail.com | |||
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| One of Us |
The coarser bead is exactly what I was getting at. The interesting part is that when it was mentioned to me, it was by men that knew without a doubt that they had to hold low, but didn't know why. | |||
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In my cups now, thinking about dim light and a Rough&Ready rear  with a Beach front  With that Rough&Ready mounted a half inch forward of the Rolling Block receiver, I might not even be able to see the hole in the disc! ... Which combo will make the bullets less likely to shoot high in the dark? A bigger-aperture peep closer to the eye will be better for sure. Lyman says of their Lyman No. 2 Tang Sight:  Besides the longer sight radius provided: "The 'peep' is also a great help to sharpen the front sight. It provides a clear view of the target and front sight and can be used when the light is too dim for other sights." What is the best front sight to go with this? Big white grampa bead or patridge painted white?  Riflecrank Internationale Permanente | |||
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Great Post... Thanks for all of the iron sight info. As RIP mentioned Rifles and Shotguns are two different breeds of cat. If a factory stock does not fit us because of our body type we do what ever it takes to line up the sights irons or scope to reach our target. Perhaps this might help with MJines question on stock fit... With shotguns our eye is the rear sight and to quote RIP "A shotgun with only a largely ignored front bead and an eyeball for sighting is a different beast, where cheek position will greatly affect POI." The Churchill method of stock fitting has the shooter standing approx 16yrds from a pattering board, with the hard focus being a dot at the center of the board. The shooter then fires the gun the instant the stock meets his cheek. For every 1 inch the center of the pattern is left right or up or down the stock needs to be moved 1/4 of and inch. As we age our body type changes, we loose or gain muscle mass we get fatter or thinner. If we have been fortunate enough to have a custom stock fitted to us those measurement may change over the course of time. To compensate for this change we can make adjustments to the way we mount the gun, add material to the stock or reach into our pocket and have stock adjustments made or a new stock. When I pick up a strange gun and throw it to my shoulder I usually have to look for the sights, but after mounting the gun numerous times the sights are there. But to get there I have had to alter my gun mount and perhaps cant the gun. Learning lots.... Thanks | |||
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The Accurate Reloading Forums THE ACCURATE RELOADING.COM FORUMS Rifles Big Bores Point of Impact Question
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