Jeff Cooper's thoughts on the subject - Note: People fell into his "dangerous game" catagory.
At this stage in the development of smallarms, we have almost abandoned the idea of metallic sights for rifles. That is to say, the gun trade has gone that route, but I personally do not follow it. I have long pointed out that I do not think a telescopic sight is the proper arrangement for dangerous game. No matter how dangerous a wild beast may be, he cannot hurt you unless he can touch you, which means that if you have to shoot to save your life, you will be working at very short range. A big, dangerous animal at short range does not present much of a sighting problem, but if you are going to set your rifle up for this situation, you should try to do it right. Specifically I think the proper iron sight for dangerous game is a ghost-ring, which is an aperture sight with a large diameter aperture and a thin rim.
Most people who think about this have arrived at the same conclusions, but just what sort of front sight is best is not so obvious. Personally I do not fancy a round bead, despite the verdict of years. A bead is quick enough, but its curved top surface is imprecise by comparison with a square post. It may be claimed that precision is not very important when shooting defensively at short range, but I do not think that means we should ignore the subject.
Traditionally, that exposed front sight out at the end of the rifle is fragile. If the shooter is not careful, he can bang it on things. Thus it is commonly protected by either ears or a hood. Those ears were originally vertical on the great M1 rifle, but some organizations reported that it was easy for a recruit to become excited and use one of the ears rather than the front sight when shooting. Thus those ears were bent outward, and this is one reasonably successful solution to the problem. Ears of any kind, however, are mud grabbers, and while one should certainly keep his rifle's muzzle out of the mud, circumstances sometimes get out of hand. Thus many military front sights are hooded by a metal shroud which passes clear over the top. This works fairly well, but it is still subject to bending and the acquisition of trash.
After many long years of study I have come up with what I think is the best solution to this matter. I like a broad, heavy, black ramp with a narrow median strip which projects about an 1/8" above the ramp and is by choice filled with flash orange pigment. The shoulders of the base ramp offer quite good protection against bumps and jars. The square inner post offers good vertical precision and the center "flash strip" offers practically instantaneous pick up. There are no ears and no hood to pick up trash. When combined with a proper rear ghost-ring, this is the best answer for "up close and personal" situations.
http://www.thesconce.com/Things to ponder...