Boresighting With A Laser

Krypton is a rare chemical element with an atomic number of 36. It is Superman’s worst enemy. Since you are not Superman, Krypton can help you make a name for yourself as a wizard at zeroing rifle scopes and electronic handgun sights. Krypton is one of the light amplifiers that make a laser a laser. It emits a green beam. Other amplifiers produce a blue or red light. There are gas lasers, chemical lasers, solid state lasers, infra-red lasers, UV lasers, X-ray lasers, pulsed lasers and constant wave lasers. Great.

But what is a laser and who dreamed it up? Suffice it to say the invention of the laser was definitely not a one-man operation. Do you remember Bell Laboratories? At one time it was the primary think tank of AT&T and operated like the legendary Skunk Works at Lockheed. That was before the Federal Government, who hasn’t managed to do anything right since the Manhattan Project, broke up AT&T. The Nobel prize-winning brains that had developed and patented so much were derailed at least temporarily.

Among their contributions up to that time were the transistor and later, at General Electric research centers, the laser diode. Try operating a laser printer, listening to a CD or watching a DVD without one. In 1953, Bell Labs Charles Townes, James P. Gordon and Herbert J. Ziegler produced the first microwave amplifier. It boosted microwaves instead of visible radiation but operated on the same principle as a laser which, basically, works by exciting and amplifying light.

In 1958, the Labs filed for a patent on its "maser." The following year, a Columbia University Grad Student, Gordon Gould, while working on his Doctorate thesis, first coined the acronym for laser: Light Ampli- On the bench in front of the kit are the adapters that screw in to the internally threaded end of the unit to secure it in the barrel. fication by Stimulated Emission of Radiation. (Go Lions!

I remember well the day our Light Blue pigskin warriors snapped the great Army team three-year winning streak with a 21 to 20 come-from-behind victory at old Baker Field. Manhattan Island reverberated with "Roar Lions Roar," the school fight song, for over a week thereafter.) Though precisely who invented the laser remains an open question, Doctor Theodore H. Maiman is credited with operating the first functioning one in 1960.

It employed a solid state, flash lamp pumped—meaning stimulated—synthetic ruby crystal grown for the purpose by Union Carbide. I had the honor and extreme pleasure of a lunch with Dr. Maiman

to discuss the possible future uses of his laser. His answer to my question was, "It’s a solution in search of a problem." To say he was modest in his response would go beyond understatement. Lasers has become an integral part of people’s lives. Applications include consumer electronics, information technology, science, bloodless surgery, heavy and light industry, entertainment, law enforcement, smart bombs, a multiplicity of other military uses and, lest I forget, the shooting sports.

The lattermost is where you all can get into the action thanks to an outfit based in Cottonwood, Arizona called Laser Lyte. If the name is new to you it probably shouldn’t be. The company was established 25 years ago and is considered the innovative and technological leader in civilian firearm laser applications. The initial one of those applications on my menu is using a laser boresighter to zero a scope already mounted on a rifle. Let’s back up to look at how that scope should be mounted first.

If the gun has been factory pre-drilled for a scope base you don’t have to be concerned about the screw holes being perfectly aligned with the bore. If otherwise is the case, making certain said alignment exists is totally on you. The bench you work on has to be leveled true. No tilting in any direction permitted. Wobbling is also outlawed. A rifle or barreled action is going to be placed on that bench after being clamped into a rifle vise. Both the vise and its contents must be trued.

A bubble-equipped Dead Center Finder (Brownells) will be used to place a mark just aft of the muzzle. Another mark will be placed on the receiver as close to the barrel breech as possible. Both marks must be made without disturbing the position of the rifle. The same is true of the line you are to draw connecting those marks for it will indicate the center bore of the barrel. I recommend using a sharp, soft lead pencil for the line. It won’t mar the barrel The laser is shipped ready to go including batteries.

As with any laser never point it toward your own or anyone’s face as permanent eye damage could result. and cleans off easily with detergent and water. Cut yourself two lengths of duct tape long enough to encircle the base and receiver. Assuming the base is a four holer, an advised choice for heavier recoiling rifles, determine and mark its center point both fore and aft. Measure the overall length of a loaded cartridge in the intended caliber.

A point on the bore center line starting at the chamber mouth and exceeding the case mouth length of the cartridge should be pencil-marked. That point indicates the primary positioning of the forward base holes. While maintaining base position with the bore center line, mark its rearmost holes on the receiver. The base should be long enough to accommodate this. Why are these location marks so vital? You do not want to drill into the chamber or the barrel extension. Not no way, not ever.

You must keep the base holes positioned over the marks. Wrapping the two strips of tape around your workpiece helps assure there’ll be no movement. I choose to gain additional assurance by using small C-clamps or large spring clamps to further secure the base to the barreled action. Once you are confident the base has been immobilized, mark the holes to be drilled using the base pre-drilled and threaded holes as your locators. You’re ready for the next step.

Remove the barreled action from the rifle vise and replace the vise with a Forster Universal Sight Mounting Fixture. The Forster is a substan- Atial tool I’ve worked with for over ten years. One reason I favor it is its durability. Others include the hardened steel 10-32, 8-40, 6-48 and 3-56 bushings provided with it that have always eliminated run out during drilling operations and the bushing coming into play during tapping that prevents cocking or breaking a tap.

I have even risked the use of a handheld power drill with my Forster and suffered no mishaps. I do prefer and here recommend transfer of the fixture to a drill press or milling/ drilling machine, however. There’s no sense risking any tainting of my wizard status. For the same reason, I further recommend hole depth limiting stops be placed on a drill despite the fact the machine tool involved is equipped with a depth-limiting feature. Back it up with a collar or other limiting means.

Take it from an old fella who’d like to keep the privilege wearing of his hard-earned, overly tall, sharply pointed headwear with the stars, crescent moons and pins that look like guns on it. There’s nothing to equal a mindless drill bit tearing up more metal than it should to knock it right off my head. That fate, of course, would never happen to all you practicing wizards and those studying to become one, so I shall continue.

Use ample cutting fluid when drilling, withdraw and clean the tap of chips frequently when threading the hole drilled. When installing the scope base screws follow the X-factor

The level can also be used to true up the rifle after the scope base has been installed. The dot is off center and blurred because the author feared the optical system of his camera might refocus the beam into his eye. To avoid this, the camera was switched from auto focus to manual, deliberately misfocused and tapped on one side as the photo was snapped. method. First, screw into left hand front hole. Second, screw into right hand rear hole.

Third, screw into right hand front hole and finally, screw into left hand rear hole. Tighten each progressively and in the same order. When the time comes later on use a blue thread-locking fluid to finish the process. Do not use any color but blue. The red stuff is so strong after curing it can jam a bolt closed permanently. Permanently, that is, until the bolt has been heated up enough to defeat the seal.

Usually, this is also hot enough to defeat the ability of any springs in the bolt to continue acting like a spring. More must happen before you bring on the laser Your customer has to shoulder the gun and bench rest it as though about to fire. The individual’s head should be tilted so the cheek is in contact with the butt stock. Make sure this positioning is all very normal, comfortable and readily maintained. No cramping or straining is permitted as it results in unintended movement.

The dominant eye is focusing over the scope base and straight down the barrel. This focus remains constant as you proceed. Buy or make a thin, flat stick along the order of a paint stirrer. Place one end on the scope base. With the pencil, start at the bottom of the stick and move it up until the end of the pencil interferes with the shooter’s line of sight. Mark that spot. Measure from the bottom of the stick to the spot you made.

Congratulations, you have just established the center points of the scope rings you’ll be installing. Scope ring height is selected accordingly. After the ring posts have been screw mounted to the base following the X-factor method, rest the chosen scope on them and loosely cap the scope with the upper ring halves. Enlist the customer again. Move the scope forward or backward until a full view of the reticle totally dominates the picture being presented through the eyepiece.

Make certain the eyepiece of the scope doesn’t sit so far back it presents any danger of recoil driving the scope back into the shooter’s face. Eye injury is possible if the precaution is ignored and a nasty cut on the bridge of the nose almost assured. Tighten down the ring halves. Do not apply thread sealant at this time. Don’t become frustrated with all the measurement details I’m dishing out and don’t rush them any time during this scope mounting process.

James Purdey and Sons take over 14 measurements before starting to fashion a stock custom fit to the purchaser of a Purdey’s Best shotgun. Each of those measurements is checked and rechecked during the making of the stock even though the buyer of the firearm may have to be flown in for a checking. No wonder a Best costs so much. How much? If you have to ask, don’t ever think about owning one. Laser Boresighter The instrument is contained in the Mini Bore Sighter (MBS) accessory kit available from Laser Lyte.

It will come out the sturdy case of the kit containing batteries. The laser emits if the switch is rotated to the on position. Do not point the large end of the laser towards anyone’s eyes as the dot from the beam will be red, intense and can do permanent damage. The only green laser made by Laser Lyte these days is their Picatinny-mountable K-15. While chances a hunting rifle will have a Picatinny rail are slim, it will undoubtedly have a barrel.

The thin end of the MBS fits into the muzzle of that barrel wearing a caliber-specific adapter. Four adapters, ranging .220 to .270, .280 to .349, .350 to .439 and .435 to .50 all have "leaves" on the order of the older, and no longer favored, Series 70 1911 collet barrel bushings, so the adapter required for the rifle you’re sweating over will be in the kit.

So will extra batteries, a bubble level doubling as a gun or scope leveler, a ring for attaching the bubble level to the business end of the MBS, a very small Allen wrench and four screws. The shorter screws are intended for the lower caliber adapters and the longer screws for the higher caliber versions. In practice, the screw is

The gain medium (1) has the ability to amplify light. Energy to amplify, or "pump," light is delivered to the medium (2) with an electrical current, light of a wave length differing from the light to be produced, a flash lamp or even another laser. The high reflector (3) is a true mirror. The output coupler (4) is also a mirror but made with properties that allow some light to exit. Every time the light is bounced back and forth between the two mirrors it passes through the medium and is further amplified.

Eventually the light will escape through the output coupler as a beam (5) which produces the familiar dot. turned through the adapter and into contact with the internal threads in the small end of the MBS. As the screw is tightened, the leaves become spread to both fill the bore and help secure the MBS in the barrel. Run a check on whether or not the scope is dead level. No, it’s not too late. You couldn’t do it previously anyway because the MBS wasn’t installed in the barrel.

Now that it has been made snug by gently pressing the MBS into the muzzle – which should be accompanied with a clockwise/counter-clockwise motion—loosen the rings enough to allow rotation of the scope. Get out your gun vise, level and resecure the rifle. Assure it and the MBS are both level by placing the ring inside the bubble fixture. If required, reposition the rifle until the bubble centers between the lines. Pick a spot on the wall about seven feet distant and turn on the laser.

Rotate and adjust the scope until its cross hairs intersect the dot. The scope is level. Turn off the laser. Apply a bit of Blue thread locking compound and tighten the rings. For the initial sighting in phase, distance from muzzle to target is 25 to 30 yards. Ideally, the range should be 100-yards for making final scope adjustments. Install he MBS, snug it into the barrel and "fire" the laser at the target. Hold the dot at the point of illumination and adjust the reticle to cover it.

The rifle is not only bore sighted, the scope is operating along dead center bore. Now REMOVE THE MBS, back off to 100 yards, bench and bag the gun and go for a three shot group forming a cloverleaf. Failed the first time? Try a few more rounds. Didn’t quite do it, eh? Well, put on your wizard hat and head back to the bench. There’s something wrong with the rifle a laser can’t cure. AG American Gunsmithing Association