Pull & Drop Gauge
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The subject of stock fitting is filled with much myth, mystery, and, sometimes, even the plain PULL & DROP unvarnished truth. The Brownells Pull and Drop Gauge provides the gunsmith with an economical and accurate GAUGE tool for measuring the basic dimensions of a gun stock. It helps you accurately duplicate dimensions from one stock to another, and fit #080-033-000 an individual stock to a shooter. The Pull and Drop Gauge will measure stock dimensions in- cluding length of pull, drop at comb and drop U|xaFAIAGy10656rzu at heel to 1/8 of an inch, and can be used to mark the stock when lowering the comb and shortening the stock. Using the Brownells Pull and Drop Gauge allows the gunsmith to easily demonstrate to the customer where custom fit- ting of the stock may be in order. BINDER RING DATA m WARNING m Never attempt to disassemble or reassemble a firearm unless you are GUNSMITHS READ & FOLLOW THESE absolutely certain that it is empty and unloaded. Visually inspect the chamber, the magazine and firing mechanism to be absolutely certain INSTRUCTIONS that no ammunition remains in the firearm. Disassembly and reas- sembly should follow the manufacturer’s instructions. If such instruc- tions are not immediately available, contact the manufacturer to see BROWNELLS if they are available. If they are not available at all, then you should consult other reference sources such as reference books or persons with sufficient knowledge. If such alternative sources are not available and 200 S. Front St. Montezuma, IA 50171 you have a need to disassemble or reassemble the firearm, you should 800-741-0015 or 641-623-4000 • www.brownells.com proceed basing your procedures on common sense and experience with World’s Largest Supplier of similarly constructed firearms. Firearms Accessories and Gunsmithing Tools.™ With regard to the use of these tools, the advice of Brownells Incor- porated is general. If there is any question as to a specific application it would be best to seek out specific advice from other sources and not solely rely on the general advice and warnings given. HOW TO USE WARNING: THIS TOOL AND THE PROCEDURES DETAILED BELOW ARE YOUR YOUR INTENDED TO BE USED ONLY BY QUALIFIED PERSONS FAMILIAR WITH IN STOCK ALTERATION TECHNIQUES, AND OBSERVING STRICT SAFETY PRECAUTIONS AT ALL TIMES. Both rifles and shotguns can be fitted using the techniques outlined below. By measuring these dimensions on our shotgun we can determine what we Factory rifle stocks are not frequently altered beyond Length Of Pull (LOP) have. The Brownells Pull and Drop Gauge is particularly useful in determin- adjustment and, in some cases, comb height adjustment to facilitate iron ing these measurements. The following illustrations show how. sight/scope sight access. In the case of a custom rifle stock, factors such as LOP, comb height (alignment to iron sights or a scope), grip size and other INSTRUCTIONS custom dimensions are incorporated into the stock during the stockmaking phase of the gun building process. Some customers will want a rifle stock Measuring Drop fitted with the same attention to detail that is necessary in a shotgun stock, THESE the following instructions apply equally to rifle and shotgun. The fit of a shotgun stock is much more critical to comfortable and accurate SAVE shooting than many suspect. Since the “rear sight” of a shotgun is actually the shooters’ eye, an ill-fitting stock is the equivalent of having the sights misaligned. The need for comfort should be addressed also. Painful shooting leads to bad shooting habits like jerking, bucking, flinching, closing the eyes and not keeping the head down on the stock. The first thing to do is define the parts of the buttstock and the terms used in establishing measurements. The following diagram shows the major terminology and relationships we will be talking about concerning gun fit: Measuring Pull Comb Heel Nose Length of Pull Now that we have some baseline measurements of the stock, we can mea- sure gun fit to the shooter and establish how to modify the stock for best fit. Toe 076-200-548 Sept. 05r © 2005 BROWNELLS, INC. MADE IN U.S.A. If we already have one shotgun that fits very well we can compare the toe to accomplish this. Place a spacer between the barrel or rib and the dimensions and make the new stock as nearly identical as possible. If we length of the straight edge that extends over the barrel. This will help don’t have another shotgun stock that fits, then we must proceed to fit maintain the pitch angle as you slide the gauge to the new pull length as this gun to the shooter. shown in the second diagram. Make sure to allow for the thickness of the Checking fit is usually done by having the gunsmith stand in front of the recoil pad, then scribe along the gauge to mark your cutting guideline. shooter and look down the barrel to check alignment of the shooter’s eye Rifles generally do not have pitch; the butt should be at a 90° angle to the to the rib or top of barrel. MAKE ABSOLUTELY CERTAIN THE FIRE- centerline of the barrel. ARM IS UNLOADED. CHECK BOTH CHAMBER AND MAGA- The next step in fitting the shotgun is to align the eye over the center of ZINE AND BE CERTAIN BOTH ARE EMPTY. A shooter working on his the sighting plane or rib. Have the shooter mount the gun, check the rela- own gun can shoulder the gun while looking at a mirror, he must also tionship of the shooting eye to the sighting plane and determine which way MAKE ABSOLUTELY CERTAIN THE FIREARM IS UNLOADED. the shooter’s head needs to move to center the eye over the rib or sighting The old established way of determining Length Of Pull is by placing the plane. Narrow or widen the comb at the point where the cheekbone and short “leg” of the Brownells Pull and Drop Gauge in the crook of the arm, cheek contact the stock to center the eye. You can narrow the comb with as per the picture, and measuring the length of the forearm to the trigger a rasp when the comb is too thick; add a cheek pad or build up the area finger. While this measurement was widely used in the past to determine with wood or epoxy and polishing/finishing to a smooth contour. Or, it is possible to “bend” the stock, adding “cast-on” or “cast-off”. Cast-off moves Pull Length the stock to the right for a right-handed shooter, cast-on moves the stock to the left, for a left-handed shooter. In the case of an expensive shotgun it may be preferable to send the stock to a professional stockmaker for bending. Whichever way it is accomplished, it is absolutely necessary to get the eye centered over the sighting plane or else the shotgun will likely shoot left, or right, of center. Next, adjust the height of the comb to position the eye correctly above the sighting plane. Once again, with the shotgun unloaded, have the shooter mount the gun. For field (game), skeet and sporting clays shooting, we usually want a “flat” shooting gun. That is one that centers the pattern of the shotgun evenly around the center of the aiming area. Raise or lower the comb height until the pupil (dark spot in the center of the eye) is nearly touching the surface of the sighting plane. To adjust, make small changes in the height of the comb, maintaining a straight comb line with frequent stops for checking fit as you go along. fit, it does not take into account such factors as facial bone structure, Trapshooters frequently like a gun to shoot a little “high” as their targets length of the neck, thickness of the chest or the type of clothing that will are usually rising as they are shot. By shooting high, the likelihood of be worn while shooting (when predictable). shooting under the target is diminished. We normally want about 60% of A more exact way of checking gun fit is to have the shooter dress ap- the pattern to hit above and 40% below the aiming mark. This can usually propriately for the circumstances under which the shotgun is expected to be accomplished by adjusting eye height above the sighting plane until the be used. There are two basic methods used to fit the gun to the shooter. iris of the eye (the colored part) is just touching the sighting plane of the Method 1 - Have the shooter close both eyes, mount the shotgun to the nor- shotgun. Again, make small changes with frequent stops to check for fit. mal shooting position and, without moving, open the eyes. The gunsmith When the stock fit is finished, use the Brownells Pull and Drop Gauge standing in front of the shooter can now determine the relationship of the to measure the finished dimensions and record them in your customer’s shooting eye to the sighting plane of the shotgun. The reason for closing file. Future guns can be altered to the same fit. the eyes is that there is a natural tendency to conform to the gun when While the above directions have addressed fitting a shotgun stock, the the eyes are open, making it difficult to assess the natural fit of the gun exact same results can be obtained when fitting a rifle stock. If the shooter to the shooter. By closing the eyes while mounting the gun we can see the is having trouble getting “down” on the stock to align the front and rear natural relationship of the shooter to the stock and eliminate the subcon- sight, the comb line can be lowered just as if lowering the comb for a shot- scious tendency to conform to the stock by the shooter.