Vision & sight blade width focus problems (target vs front sight)
#1
Posted 20 December 2001 - 05:52 AM
But no mention of the affect of the front sight blade WIDTH WRT how much 'white space' you see in the rear sight notch.
I started aiming at the wall while cogitating the things I read, and I just realized that my sights have very little white space, which makes it very very hard to pick up the front sight quickly (given my previously mentioned problems).
I think that if my index was perfect, I could just use the rear notch alone. Might shooot high or low, but the lateral alignment would be there. Wish I had a sight tool; I could try installing a narrower blade. This Kimber has a dovetailed front sight... Do they make different widths for it?
I also noted that the serrations on the front sight are only visible when a strong light comes from a particular angle & direction. So they are not a reliable way to gain a focus on the blade.
The crummy lighting on the indoor range is a worst case scenario too. But it ought to force me to index!
#2
Posted 20 December 2001 - 02:01 PM
In the in-depth book "Competition shooting" by (?) A. L. Yur ev (retired Russian Olympic shooting coach), he details the results of extensive study on that exact question. To nutshell it, you'd like to see, at minimum, a "perceived" (not measured) one-half of the front site's width on each side of the blade. (For my arm's length, my current .115 front and .135 rear is real close.) And, the maximum is considered to be a full front site's width on each side of the blade. Now, these studies relate to International Rapid Fire, where the entire sight picture fits on a huge black target, so it may not correspond to exactly what we do. I've found, however, that it seems to be right on for me. It doesn't really matter how "big" the sites are, your body will naturally attempt to align them a the exact spot you intend. I've found, after MANY experimental sessions, that I CONFIRM perfect alignment much, much quicker with a big, bold, sight picture. With small light bars, the body-mind just spends too much time trying to get them aligned "just right." It's one more of those concepts that goes against our natural instincts.
be
#3
Posted 20 December 2001 - 02:46 PM
#4
Posted 06 January 2002 - 08:32 PM
#10
Posted 13 January 2002 - 03:29 PM
#11
Posted 13 January 2002 - 07:34 PM
I took about .015" off my Dawson fiber-optic front post. It's now at .120" with the rear Bo-Mar notch at .138"
The "light bars" on either side of the front post are perfect (1/2 the thickness of the post) at my arms length (6'-1" wingspan)
A little Brownells 444 blueing liquid, and it looks like one of 'dem perfessionawls did't ! :)
#12
Posted 17 January 2002 - 08:41 PM
According to the human factors engineer, for fast alignment, you need to see enough light at each side that the bit of wobble you have doesn't pinch out the light significantly. He was unsure about the vertical, but thought patridge was probably best. His comment on the dot front was wondering how the dot would be indexed against the rear sight unless it had dots, too, and in the same apparent position. I told him on precision shots one would use the top of the front sight and he said he thought the dot would make people shoot high if they were in a hurry (is this true?).
The Russian shooting coach BE mentions, A. A. Yer'yev, also reported that the most winning rear sight in the various Olympic pistol shooting events, by 2 to 1, had a U shaped notch, not a square bottomed notch (that makes the "half ghost ring" over 40 years old).
The Russians found that a front sight that was the same or slightly wider than the apparent width of the bullseye gives the best accuracy with the least eye fatigue, but because Olympic pistol targets have a wide bullseye, they found that rule impractical to implement for pistols. Instead, they settled on a front sight, 0.125-0.145 wide, which their experience has shown to give maximum accuracy and minimum eye fatigue.
A quick calc shows an 6" plate at 50 yds would be about the visible width of a 0.093 front sight (with sight 28" from eye). An 8" plate at 50 yds would equal a 0.124 front sight at 28".
I run a 0.145 rear notch and recently narrowed my front sight from 0.125 to 0.097, which I have found much easier to see with my aging eyes. From the looks of it I am running at the 1:3 end of the scale rather than the 1:2. Given all this, maybe I should have opened up the rear notch, instead. Might be worth a try, but I am probably already in the ballpark.
#13
Posted 18 January 2002 - 01:28 AM
I'd like to add another aspect for your concideration, I hope my description is not too confusing;
I've typically used a front/rear sight ratio of about .8, previously a .09" front and .112" rear, now I'm trying Brians recipie, which is a little tighter at .85
The idea of an acceptable sight picture, as opposed to a perfect one has been discussed.
I think it becomes progressively harder to judge the adequacy of a sight picture at high speed as that ratio declines.
With my old sight picture, just seeing the front post through the rear results in an A out to 12 yards (laterally that is, the worst vertical error through the rear notch would score a low C/D on a Classic target)
For me that is a major concideration and it makes shooting much faster
P.D.
#14
Posted 18 January 2002 - 02:32 PM
You described your previous sight setup as .090/.112, which is a calculated 0.80 and approximately a visual 0.46 (or 2.2:1 if we use the apparent rear to front ratio like the Russians do). That gives you a bit more than half a front blade's width on each side. If I understand you right, you also said this setup gave you an A out to 12 yds (laterally). You also said you are now using Brian's setup, which is 0.115/0.135, or 0.85 calculated, 0.49 visually (2.04:1 Russian ratio). All this seems straightforward.
Then you said "I think it becomes progressively harder to judge the adequacy of a sight picture at high speed as that ratio declines." That's where you lost me. Did you mean it was harder with your old sight picture than your new one, or vice versa?
I agree with you that it really helps to know just how far off you are when the blade is at the edge of the notch, and at what distances that is acceptable.
#15
Posted 18 January 2002 - 03:16 PM
I want one free for coming up with the idea.
#16
Posted 18 January 2002 - 03:47 PM
just seeing the blade within the notch with your sight picture (.67 ratio) is less likely to result in an A hit than the tighter sight picture I described.
Its a trade off, I'm sure yours would be faster to align, but mine requires less aligning
Its only my opinion, but it is something to concider when choosing a sight picture, obviously the conditions vary conciderably in IPSC unlike ISSF/UIT.
I also have rapid fire gun, though I haven't shot it seriously yet, i did start to adjust the sight picture towards a more typical IPSC set up. As it came the front post pretty much filed the rear notch
P.D.
#17
Posted 18 January 2002 - 05:08 PM
When I use my new sight setup I can almost always see some white space unless my index is way off. I am learning to see what I need to see with the new sight setup, and its a little different than what I used to use. But for me its easier to use and faster than the old one. I just know that for an A at 12 yds I need a bit of white all around. I am finding that easier to achieve than if the front sight has pinched out the light on one side, which it often did with the old setup (and my aging eyes).
#19
Posted 26 April 2002 - 12:44 PM
Dangit! I've been looking for sights allowing more light through for my Kimber (0.110 front, 0.114 rear) and my Kahr (0.142 front, 0.152 rear).
It looks like EVERYBODY knows that there should be more of a difference, yet the sights came that way, and when I call about replacements, Heinie, Bo-mar, Novak, all tell me their replacements have "about the same sight picture as the factory sights". WTF!!! With an M-16, that front sight is floating in an OCEAN of space surrounded by the rear aperture, but eyes can still center it.
It's not like it really would be harder to cut a larger notch.
Guess I'll have to go get a file. What sort would you recommend (as far a coarseness)?
Thanks for letting me vent,
DogmaDog
#20
Posted 29 April 2002 - 07:17 AM
I widened the factory fixed 3-dot rear notch on my Commander from .125 to .150, keeping the front at .125. This has given me a very fast sight alignment. I did the rear notch because it was the easiest to modify. I took a flat file and ground flat one of the edges so I wouldn't change the depth of the notch. I did one side at a time, measuring the width often so as to remove the same amount from each side. This kept the windage from changing.
I'm still able to keep all of my rounds in an 8 inch circle at 25yrds and somewhat consistantly hit bowling pins at 40+.
Remember I'm still a BEginner but I recently did a 7yrd Bill Drill that had 2 targets side by side, one being inverted, six rounds each w/a mag change between in just over 9 seconds with all A's. I'm also shooting a lot more A's than C's in our regular COF.
Thanks again for the Great Forums.
Joe
#21
Posted 20 May 2002 - 11:31 AM
#23
Posted 24 February 2005 - 11:36 AM
For focusing on the front sight, I wonder if the smallest ghost ring/aperture rear might help. I suggest this because when you switch apertures on an AR, the front sight post and/or a red dot will always look sharper and more in focus when you use the smaller aperture.
#24
Posted 24 February 2005 - 12:08 PM
Scott Springer e-mail me here
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#25
Posted 22 April 2005 - 07:03 PM
That is so ironic you say that. When I was working my way up and made GM in Limited and shooting my best, I was shooting my STI with a .070 front and standard .110 (I believe) rear Bomar. I loved it and felt very fast with it. I must have been doing fairly well cause I made GM with it. I'm sure shooting my STI made some difference also.
I took a break from shooting and concentrated on work (LEO/SWAT) for about 1-2 years and shot more tactically with work related exercises. About6 months ago, I got back into IPSC shooting and have been playing in Production with my Glock. I really like it and have tried different sight setups, but havent found one I really like as much as my .070 front. It's funny you say that, because I was thinking about narrowing my front sight from the .095 it is now back to .070 on my Glock and seeing what happens. Also, I've been shooting with both eyes open instead of one eye closed. I'm actually more accurate and have much less trigger jerking with both eyes open and I'm much more visual. I also starting to get faster with as I get used to both eyes.

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