Front sight/ Rear sight width ratio.

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I was at the range before work yesterday morning doing some speed drills with my Kimber 9mm 1911.

At one point I noted that some of my shots were going left, out of the A zone at 15 meters. I slowed down my shooting and then noticed that there was very little daylight each side of the front sight at that range. Speeding up again I saw that I was favouring the right side of the front sight a little and decided that I would widen the rear sight a bit to see if the leftward shots improved.

Afterwards I was sitting outside the Club room with a few of the guys and told them what had happened. I then mentioned that some of the best shooting I had ever done was with my Springfield .45, before I put on adjustable sights. The rear sight notch seemed to be wide enough to drive a Mack truck through while the front sight had been this very small nub on the end of the slide. The last time I shot the pistol with those sights I scored 26 A’s and 6 C’s on two co secutive 32 round courses of fire.

One of the others, a very experienced shooter, said that he always widened his rear sight to the point that it was twice as wide as his front sight.

Getting home today in daylight I headed out to the shed where I measured the width of the Kimber’s front sight at 0.1395”. The notch in the rear sight mic’d out to 0.1480”. Using a small needle file I widened the rear notch to 0.1530”, which seems ample to me. I can see daylight well on both sides of the front sight and on Wednesday I’ll test it out. (I was pretty careful to take the same number f file strokes each side, but a bit of windage adjustment may be needed).

But it made me think, what ratio between front and rear sights do other shooters like/use? And does it really make a difference?
 
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you really don't want much light on either side of the front sight. Perceiving a "sliver" of light will provide a more accurate sight picture than a wide swath of light which will allow for more angular error.

One thought on group sifting might be the lighting angle on the sights. Your groups will tend to shift based on the light hitting one side of the sight or the other. You will see this commonly in covered firing positions with overhead lighting that is off to the side of the shooter.

For rapid targeting you may consider using a three dot system.
 
It is probably your eyes. For combat or faster shooting you did the right thing for the way you shoot. I can shoot a target plenty good. But not with a white outline or a red ramp or a three dot system. I see a black outline better. Most of my better targets are orange. In daylight a red ramp is the color white. I widened the rear blade on one of my 1911 45s with a fixed sight and hitting a can at 20+ yards is easier and faster. Find the load you intend to shoot before the final file job and do it on the bench without people bothering you if you can.:)
 
As I got older and my eye sight wasn't improving, I tried a narrow front sight ( .110 rather than .125 ) on a couple of my handguns. Some say it is easier to pick up the sights, and / or if your eyes aren't as good, if you have more daylight around the front sight.

( several places make different width front sights , Dawson is the first one that comes to mind, and the front sight is usually easier to replace than modify the rear sight )

I've heard some folks refer to them as "speed sights", bigger window = faster shooting.

Personally I didn't find this true. For me it seemed like I had more room for error. If the front sight was in the window and the front sight was on the 'A' zone , I'd make the shot..
So , if the front sight was shading the left side of the window and I was shading the left side of the 'A' zone ,, I'd get a big fat 'C'..:eek:

So I went back to the wider front sight with just a little daylight on each side.. Works better for me..

But, I do know several shooters that prefer the .110 or narrow front sight. If that is what is working for you ,,, go for it.. :)

Guess I'm just an old dog that you can't teach new tricks.. :D

( edit: I have modified some of my rear sights. For some reason , I'm not sure why, I prefer a deeper channel on the rear sight. I like to see more of the front sight in the rear window. So, I have replaced
and/or used a file to make the slots deeper. Especially S&W revolver rear sight. )
 
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This is advice I give for IDPA shooters; it comes from Dawson Precision

Which width front sight do I need?
Most action shooters go with a .100" to .105" wide front sight.

What rear notch width do I need?
Great to good eyesight should use .115" to .125" rear notch width. Average eyesight should use .135" to .145" rear notch width. Poor eyesight should use .155" rear notch width. Remember, the more light in the notch the the easier it is to see front and rear sight separation.
 
you really don't want much light on either side of the front sight. Perceiving a "sliver" of light will provide a more accurate sight picture than a wide swath of light which will allow for more angular error.

One thought on group sifting might be the lighting angle on the sights. Your groups will tend to shift based on the light hitting one side of the sight or the other. You will see this commonly in covered firing positions with overhead lighting that is off to the side of the shooter.

For rapid targeting you may consider using a three dot system.

I have found over the years that I prefer plain black sights. I have a red dot in the front sight of my Springfield .45 which I black out as my shooting falls away if I am conc3ntrating on 5he dot rather than the front sight position. And I have done the same to my,pistols with the 3 dot system. For some reason they just don’t work for me.
 
This is advice I give for IDPA shooters; it comes from Dawson Precision

Which width front sight do I need?
Most action shooters go with a .100" to .105" wide front sight.

What rear notch width do I need?
Great to good eyesight should use .115" to .125" rear notch width. Aver’age eyesight should use .135" to .145" rear notch width. Poor eyesight should use .155" rear notch width. Remember, the more light in the notch the the easier it is to see front and rear sight separation.

I was born with both myopia and astigmatism. I had laser surgery when it became available here in 1995. Individually both my eyes fail the test for a driving license but together they pass.

After more than 20years without vision aids I took to wearing soft contact lenses a couple of years go for work, long distance (more than 30 min) driving and for shooting, and glasses for watching TV in the evening.

Oh, and I am left eye dominant but shoot better using my right eye. So I guess my .1395 front and .1530 rear are about right for me.
 
A non scientific attempt.

Okay, I know my iTarget Pro is hardly range time, but the 3/4" 10 ring at 14' (I know the screenshot says 10" but I forgot to adjust it correctly) is roughly the maximum width of an IPSC A zone at 20-25 yards. And it is the best I can do until I get to the range tomorrow.

When compared to the trainings shots last week the times are not too dissimilar as are the overall scores (I wish I could get the damm thing calibrated properly but every time I place my phone in the holder it changes). But it does seem that the groups are a fraction tighter with the wider sight notch today.

Well that's what I'm telling myself anyway.

Oh, the 7 second shot? The screen failed to record the laser on the first shot. I had to recock the hammer and fire again.
 

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Frequently, widening the rear sight improves speed and accuracy.

I’ve often taken a file to the rear sight and noticeably improved my shooting with that gun.

I can’t specify a ratio: I can only say that I know of no instance in which opening up the rear sight failed to improve shooting speed and accuracy.

Blacking out dots helps as well.
 
A back injury (muscle spasm) the morning I was due to go to the range to try the wider rear sight out, saw me with only enough range time to check the sights after filing (3 clicks right needed) before the start of today’s Level III IPSC shoot.

With the exception of one stage, where a factory round jammed in the chamber with the slide not in battery causing an end to the stage with 3 1/2 target’s unshot (a total of 7 misses and 3 procedural for failing to engage, a 0 stage), my shooting was pretty good. I was regularly outshooting another competitor who easily outshot me a few months ago.

How much of that was down to shooting the 9mm instead of the 45 I can’t saybut my gut impression is that the rear sight could be widened even more.
 
Your eyesight is just that;yours!
A wider rear sight(or narrower front)is better for quick acquisition(IPSC and the likes)while a narrower light is better for slow deliberate precision shooting.But a lot of light for you might be not so much for my eyes.
The best thing I've done these last 10 years for shooting was to go ask my oculist to make me a single prescription glass unifocal at the lenght of my arm+a 6''bbl handgun.The other glass(in my case the left one as I'm a right dominating eye)was simply sandblasted opaque white.
My scores improved immediatly and it is not costly(the trick here to save $$$ is to use the mounts of an old pair of glasses)!
From there on,I was able to determinate what amount of light I like best.Hope it helps you as much as it did to me.
 
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After the second day of a weekend competition yesterday I took the opportunity to speak to a fellow competitor who is a Master grade IPSC shooter. A tool and die maker by trade he has a reputation as a very good 1911 gunsmith.

While I initially wanted to speak to him about trigger work, I asked his opinion of the sight width. He felt that the rear sight was wide enough but that the front sight was too wide. He estimated the width as near 4mm and felt that a 3mm width would be better.

After arriving home early this morning I stripped the pistol for cleaning and set to a little more sight adjustment.

I had found the right side of the rear sight was not quite vertical, there was a slight lean inwards at the top, so a few light stokes with a very fine file was all it needed.

The front sight mic’d out at 3.59mm so I carefully set about narrowing this down to 3.15mm. After setting the slide back on the frame and trying a site picture I felt that this was as narrow as I want to go at this time.

Of course the gun will now require some more sight adjustments to get back to POA/POI but that won’t take long.
 
For quick sight acquisition I like the old Sig dot the i method. The two dots on the rear sight competes with the front for focus. I shoot Kahrs in 9 and 45 and find this "dot the i" method very quick to acquire for fast shooting accurately. The 3 dot system became popular with the introduction of night sights. The Heinie straight 8 is a better system for me. I also prefer the open rear on SD guns. My 44s or field guns have narrow blades on both ends of the weapon.
 
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