Gun Digest 2011. Dan Shideler
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Nineteenth century iron sights proved so useful that they remain with us today. Consider the Marble Arms threesome of full buckhorn, semi-buckhorn, and flat-top rear sights. Dovetailed into the barrel, these open irons are adjusted for windage by drifting left or right, elevation accomplished via a double step elevator (ladder). You drift the front sight left to hit right, right to hit left, rear sight up for higher, down for lower bullet impact. Simple and effective. All three have white enamel diamonds for center reference with reversible U- or V-notches. The Marble open rear sight is a prime example of the family. But there are scores of others on new rifles as well as myriad after-market choices.
A good look at an elevator bar, also called a ladder, beneath an open iron sight. The notches are used to change the height of the sight, going up to hit higher, down to hit lower. The notches do not have a specific value.
The justly-renowned receiver-mounted Lyman Peep Sight.
Rifle iron sight variation over time is an interesting study. But management of these sights is imperative for in-the-field results. The glass sight magnifies the image, which in turn increases perceived rifle movement. The rifleman immediately discovers that if he or she wants to hit that target, a better stance with greater control is demanded — sitting, kneeling, prone, hasty sling (carry strap or sling slipped through arm) or, better, a solid rest, be it the top strut of a packframe or over a log or boulder. The iron sight can give a false sense of rifle steadiness because it lacks magnification, leading the shooter to “hold sloppy.” I once found a dandy Marlin half-magazine 336 in .32 Winchester Special. Groups were OK with original irons. Adding a Lyman micrometer “peep” provided honest 1.5-inch and smaller patterns at 100 yards.
As a young firefighter on the Arizona/Mexico border I met two old miners who loved to show off their .30-30 skills. They were good. Both said they never “saw” their sights. They relied on “snap-shooting.” Fact is, the bullet can only go where the sights are “looking.” These two marksmen, experts through years of practice, were certainly seeing their sights. They also knew that if their carbines fell prey to wagging this way and that way, the result would be an errant bullet. Even offhand, they respected the equation of “shaky equals miss – steady equals hit.” The iron-sighted rifle must be treated to the same control rules as the scoped rifle. This is the rule: best possible rifle control followed by clear and precise sight picture, and finally the same careful trigger squeeze given the scoped rifle.
Here is the Ghost Ring Rear sight mounted on an older Model 336 Marlin Texan .30-30. It is a highly effective and very fast iron sight option.
Proper sight picture means a bold contrast between the front sight and the target — be that target a bull’s eye or bull moose. The front sight must be clearly distinguishable, not blended into the target. Two types of sight picture are six o-clock and dead-center. Six o’clock has top of front sight optically “sitting” directly below the intended point of impact. Dead-center has front sight optically right on top of the target. I prefer six o’clock with peep, dead-center with open irons.
Front sight coloration can be important for contrast. Colors include gold (copper alloy), white, ivory, and black, along with every imaginable hue from orange to red, blue, yellow, and pink. Bead size is also important. Prevalent dimensions are 1/16-, 3/32-, and 1/8-inch, the latter fast at very close range, but too coarse for distance because it covers too much target.
An example of front sight color importance is the White Stripe from SX Sight Systems, which is visible against all backgrounds: from plains, tundra, thickets, black timber, mountain canyons, swamps to the treeless tops of sheep country. Lighted from behind, the white stripe stands out. Lighted from the front, the whole sight appears solid black. The sight picture of this peep/ post combination prints point of impact two to three inches above the top of the post at 100 yards for .30-30-class muzzle velocities. Place the top of the post mid-chest on deer-sized game at 100 yards and the bullet strikes a little high, but well within the vitals. At 200 yards, given modern .30-30 ballistics, the flying missile falls a hand-width below the top of the post, but again within the chest region. While today’s marksmen consistently hit targets at 1,000 yards and beyond with iron-sighted rifles, as witnessed at any blackpowder cartridge match, my personal outside limit is about 200 yards with irons on big game, rangefinder verified when practical.
The open iron demands triple “visual accommodation,” the eye focusing on three planes: rear sight, front sight and target. Smart shooters learn to clearly focus on only two of the three: front sight/target. Of course the front sight must be optically centered in the notch of the rear sight for alignment. But with training and practice, the shooter learns to deal with a slightly blurred rear sight while maintaining a sharp front sight on target picture. When a SWAT team commander trained me to be a better marksman, he had me repeat “front sight-target; front sight-target; front sight-target” as the key to precise bullet delivery with open iron sights. Frame of reference is important. If the front sight optically overfills the rear sight notch, it is impossible to align it properly. It’s best to have a glint of light, if ever so minute, on either side of the front sight as it appears in the notch in order to assure that it is centered.
The peep sight requires only two points of visual concentration: front sight/target. Newcomers to the aperture sight work hard trying to optically locate the front sight in the center of the hole. This conscious level of aiming with the peep tramples on its simplicity and effectiveness. The human eye naturally seeks out the point of brightest light, pinpointing the front sight in the hole “automatically.” Ghost Ring rear sights come with a 191-inch and .230-inch inside diameter apertures. These are big. But as O’Connor pointed out, he removed the disc from his Lyman peep sights entirely, leaving a huge hole with negligible diminishment of group size. The name, Ghost Ring, tells it all. The rear sight (aperture) becomes nothing more than a halo to be ignored. It is supposed to look fuzzy. Simply line up that front sight on the target and squeeze off the shot. Work hard, and you lose. Let your natural eyesight take over, and you win.
The famous Lyman folding rear sight is standard on many factory rifles.
A good example of a semi-buckhorn sight on an old-time Model 94 Winchester. The horns almost make it to full buckhorn status, but not quite.
When sighting in, even when going for the dead-center hold, I begin with six o-clock because it offers a more specific aiming point: a bull’s eye sitting on top of a front sight. For dead-center sighting, the group falls just below the bull’s eye. Sighting in to zero at the base of the bull, the rifle will be sighted in for the dead-center hold. The true six o’clock hold, with bull’s eye optically “sitting right on top of” the front sight, the bullet strikes just above the aiming point. This allows the target to remain visible, rather than be covered by the front sight. Aperture sights on my Marlin rifles in .30-30, .32 Winchester Special, and .38-55 are sighted to group about