I started this in response to a posting over on THR well over a year ago - Feb 2004 in fact.... and a question was asked -
Thinking of Kurt (Shotgun Willie) and one or two others who have joined our ranks - new or relatively new to handgun shooting, it seemed worth copying for folks here - much applies to open sights on rifles too of course and is included. I made basic diagrams but they hopefully help explain a bit.How's about definitions of a sight picture, re: iron sights, proper vs. improper, preferably with graphic representations?
Define flash sight picture.
Explain different sight types, i.e. peep, buckhorn, Patridge, ghost ring, night sights, etc., once again with helpful graphics.
I have yet to clarify re ''Flash Sight Picture'' although I am assuming for now this means that ultra brief sight picture aquired after a fast draw and when there is a rapid target engagement. This is where grip ''muscle memory'' comes into play with a familiar weapon, such that sighting error is minimal even without adjustment.
Let's though primarily here deal with aspects of open (or ''iron'') sights, and look at the list. There is in fact as I see it, some overlap and we can simplify somewhat. Overall I am giving emphasis to handguns, but much applies to rifles also, naturally.
1] Basic non-adjustable iron sights as we might find on a handgun ... either having a rectangular notch at the rear or a ''vee'' and the foresight being probably a simple blade, sometimes with a taper toward the top. On a rifle we might see much the same except there will usually be some provision at least for rear sight adjustment .. usually in elevation. Sometimes a foresight on a rifle permits windage adjustment. Unless corrected on it .. I regard this sighting as standard ''Buckhorn''.
2] Patridge is a sight type I associate with handguns and really only means (in a generic sense anyways) sophisticated quality sights having adjustments available .. and this on the rearsight, with elevation and windage. IIRC there are examples, such as I believe on the 2nd generation S&W 686's ... where the foresight has available elevation adjustment.
3] Night Sights I am treating as being of the ''Tritium'' type .... whereby inserts in the sight body emit light thru low level radiation ...... most usefully employed on defensive handguns. Beyond these of course are the true ''Night Vision'' sighting systems, utilizing electronics for amplification of photons - for the most part showing on a screen with the characteristic green image. These are almost ''see-in-the-dark'' devices.
4] One sight system H_R_G didn't mention but which is very useful (I love them) are the laser add-ons. My personal preference is for the Crimson Trace grips .... which come into their own once light levels drop. They do NOT replace the open sights .. but they DO provide an invaluable adjunct to sighting in low light.
5] Peep and Ghost sights are in some ways in a similar category, as also are what I choose to label Match sights. These all utilize a rear aperture in some way, and the diagrams that follow further down will attempt to distinguish between them. The Peep sight is well exampled by the aperture found on an Enfield MkV Jungle Carbine. It is simply a hole in a piece of metal! The Enfield has one simple one for basic 100yd zero .... and then with a flip-up brought into play, another simple aperture but with elevation adjustment for longer ranges. They work well!
The ''Ghost'' sight principle is similar but tends to employ a large aperture with quite modest ''framing'' ... such that it does appear to be a ring. When in use, the ring becomes a blur but acts to frame the foresight picture and the shooter naturally tends to place the foresight in the center of this ''ghostly'' circle. It makes for fast aquisition and works very well for many people. Popular on many lever action carbines.
The ''Match'' as I choose to call them (again we are talking rifle really)... are again aperture in type but the rear sight has 1/4 MOA clicks on a vernier thread, to adjust for elevation and windage... so adjustment is very precise. ''Parker Hale'' were makers of fine match sights of this type. The aperture itself is usually contained within quite a lage housing about the size of a dime and frequently is a disc offering a choice of about six diameters of hole ... to suit both the shooter and the light level. Commonly also with match type sights, the foresight can also be an aperture ... making provision often for choice of insert size and the whole system relying on centering concentric circles with the target also centered.. I used this system on my match BSA MkII and it is exceptionally good.
Now to actual sighting .... the useage of open sights and what can go wrong. This is very simplified and quite unnecessary reading for those with experience. It is aimed (oops, can we call that a pun!) ... at relative newcomers ... as a reminder to help them know what to watch out for.
Each small three-diagram set that follows, shows one category of sight picture and covers three bases ...
a) - The ideal picture as it should appear (and be maintained!) ....
b) - The foresight allowed to go high (thus the shot will impact high) .....
c) - Lateral deviation with the foresight in the left side of the rear sight (thus the shot will impact to the left).
Obviously b) and c) can combine in any permutation!!
It is perhaps worth adding - I happen to favor ''plenty of daylight'' around the foresight with open sights of the rectangular notch or, the ''vee'' variety .. it seems to make for a better picture and enhances accuracy IMO - what it means is having either a thinner foresight blade and/or a wider rear sight notch. Not all may agree. Furthermore, there are many sights now that have dots of paint added .. two at the rear on each ''shoulder'' of the rearsight and one on the rear face of the foresight blade ...... I find them very helpful for rapid shooting.
OK, enough waffle ... now some diagrams. As I said ... simplified and sorry no photographs right now of actual sight examples.
Rectangular notch rear and blade front.........
''Vee'' notch rear and blade front - (forsight here shown as tapered)........
Rectangular notch rear and blade front, with dots.........
Simple aperture (peep) and blade front ......
''Ghost'' ring and blade front.........
''Match'' rear aperture, with front sight aperture
It should be apparent, that in order to maintain a good sight picture there should no influencing factors to disturb it once aquired. The most common factor that does give problems for many is trigger useage ..... and coupled with that various faults in eye focussing and flinching too.
Trigger - Let us assume your trigger is reasonable on poundage, and has no creep to impair smooth travel. We'll also for convenience ignore free play and over-travel matters. The critical factor above all is the RELEASE ..... that is the moment when the best of sight pictures can be ruined. This is in fact another whole subject, tho much has been written on it elsewhere. Suffice it to say here, and as I try to explain to beginners ..... the shot should go with the thought ... ''oh, it's gone''.!! Force it to go and there is usually a problem. This applies for rifle and handgun but .. it is worth remembering that with short sight bases on handguns ... errors are effectively way bigger than realized if the sight picture is disturbed.
Focus - At the moment of release, the sight picture should be all that is held in focus (if your eyes still young enough!! :p ). The target should be a blur. Let focus stray onto the target and in an instant the sight picture can become aberrant and accuracy is lost. It's worth a reminder that we are still talking open sights .. ''scopes'' and ''red dots'' do not present these problems the same.
Flinch - another classic problem .. it ties in with trigger useage. It could as well be named ''fear of recoil'' ...... and can be almost any muscle action that either changes grip, trigger finger useage, or instances where the head is moved back. Again another whole subject in itself.
This has purposely been kept real simple. As I said before it is not for those who are experienced, unless as a useful reminder! :p !! It might tho I hope encourage those new to shooting, and handguns in particular .. to retain mental pictures of the ''correct'' sight picture and discipline themselves to give this all their concentration as they practice. A good command of sight control, along with smoothness of all other operation ... WILL yield better results ... guaranteed. :)
I may well have omitted some things ... do please mention anyone who sees important gaps, but this is only intended as a simple ''primer''.
Oh and to add - a ''real'' pic - of a handgun sight picture as it should appear.