the gunshop, we used to sell a large number of Mossberg shotguns for defense use. The last thing someone buying an eight-shot shotgun needs or wants is a duck plug. I ended up with a drawer full of them, and used them for plugging stock holes under pads. Press the dowel into place and tap it home with a hammer. Leave the stock clamped vertically until the epoxy has set.
Once set, cut the dowel as flush as you can and sand the stock smooth. If you haven't already, remove the masking tape. Use a compatible stock finish to seal the end of the wood. If you don't seal the stock, the edges of your stock will gradually warp from the moisture that enters from the bare surface.
Drill your new pad holes. To cut the pad for the screws, press a drift punch into the screw hole from the back side, and use a razor blade to slit the pad. Place a drop of synthetic lubricant on the slit and press the screw through. Rub the threads of the screw with bar soap. Wipe a little of the same synthetic lubricant on your screwdriver blade and turn the screws tight into the stock. You've finished the clean part.
Place three layers of masking tape on the stock flush with the pad. Use a felt-tip marker to draw a zig-zag pattern on the top layer of tape. To grind the pad flush you'll need a belt or disk sander. For your own protection you'll need glasses or goggles, a breathing mask, hearing protection and a bright light. The rest of the room would benefit from a Shop-Vac and drop cloths. Spread the cloths over your bench, gun rack, shelves and anything else that would be a hassle to vacuum. If you can, attach the Shop-Vac to the sander. Stand the light over the grinder or sander so you will have a good view of the work.
Pad grinding is noisy, messy, smelly work that you must do perfectly. You do not want to be interrupted while grinding. If you approach the task with a heavy hand you can “kiss” the stock with the sanding belt, and spend a couple of hours touching up the wood you marked. Even if you are installing a pad in an unfinished stock, hitting the stock with the belt can create marks that you'll spend extra time sanding out. Be patient. Stand to the side of the belt sander, with the light on the other side. Hold the stock by the pistol grip and near the pad. While holding the near surface of the stock parallel to the running belt, press the pad against the belt. To prevent flat spots, roll the pad against the belt, following the curve of the side of the stock. You do not want to press too hard, as you will heat the pad and the belt might slip. Gradually grind down the pad, following the curve of the stock, until you are scuffing the top layer of masking tape. Once the top layer is evenly scuffed, remove it. Mark the second layer with the felt tip pen and sand until it is scuffed. Repeat on the third layer.
With the sides sanded down, place a strip of tape over each of the heel and toe and blend them into the curve of the sides.
Turn off the belt sander. Clean up the shop. Sweep and vacuum the floors, take the drop cloths out and shake them off, brush off your clothes and maybe even take a shower. When doing pads commercially, I preferred to do them one day a week, and wait until after lunch. I would prep all the pad jobs ahead of time, and then spend an afternoon grinding. That way I had to put up with rubber dust one afternoon a week, instead of several days a week during the busy season.
The last part of fitting the pad is to remove the belt sander marks from the pad. Even with a light touch and steady movement, you'll have flat spots. Sit down in a comfortable chair with a large second cut file. Hold the stock in your lap (you'll definitely want an apron on for this) with your left hand. Place your thumb against the stock at the edge of the pad. Place the safe edge of the file against your thumb, and using your thumb as a stop, file the pad smooth. Once smooth and blended all around, a fingertip's worth of linseed oil will darken and even the appearance of the pad edge. If you are using a Kick Eeze sorbothane pad and want the bright synthetic look, then don't apply the linseed oil.
If you scratch your stock, or want to refinish it, you may need stock stains. With them you can make the scratch color match the rest. If refinishing, you can make the stock look the way you want it to.
Reinstall the stock on the receiver. If you have to remove the pad to reinstall the stock, shift the pad around until it is flush all around when you tighten it. The screw holes in the pad have enough room in them that the pad might shift a little bit when tightening, and you want it perfect.
The location of the cheekpiece determines where the pattern hits. Rarely will you be faced with the problem of the cheekpiece being too high. I ran into it a few times, and in all cases the shooter had a large, round face. The size and shape of their face positioned the stock too far away from and down from their eye, and they could not squeeze in tight enough to see the bead properly. The patterns would strike high of the mark. Sometimes too high even for a trap gun.
Even if you do not mar your stock installing a recoil pad, keeping it looking good when you use it may take some effort. The only other choice is to not use the gun. What good is that?
Drop is the distance between the top of the stock and the line of the rib or bore. The rib is easier to measure, but you can calculate the bore-drop by measuring from the rib to the chamber center.
To tell if you see the bead properly, we have to define “proper.” Proper is a repeatable view of the bead, where the bead gives you a predictable location for the pattern. Proper view depends on pattern impact, and to pattern your shotgun you'll have to go to Chapter Six. Take the empty shotgun and place the buttplate to your shoulder in your shooting position. Look down the rib or barrel. Do you see just the bead, sitting on top of the visual image of the receiver? Good. Is the bead straight down the center of the rib or barrel? Also good. If you see large amounts of the rib or barrel, or your view to the bead is not down the centerline, your cheek-piece may be too high or thick. Since we are not interested in surgically altering your face, we have to change the stock.
We can see here that this stock has 1-¾ inches of drop, a straight stock by many standards. Half a century ago, many stocks would have had more than 2-½ inches of drop.
Trap is more of un aiming game than other shotgun games are. However, given a comb that is too high (or a face that is too round) we would also see the patterns striking the pattern board too high on the Churchill method.
Before you go altering your handsome stock, practice on another. I have worked on a large number of Mossberg shotguns through the years. Partly because they are quite popular in Michigan, and could be obtained cheaply. Also, spare parts are easy to obtain, so if I screwed up a part I could quickly replace it. To alter your stock you'll need cabinet makers pattern rasps from Brownells, sandpaper and stock finish that matches the current finish and a china pencil. Place the shotgun to your shoulder and hold it there with your left hand. With your right hand reach up with the china pencil and mark the comb just in front of and behind your cheek. With the rasp start removing wood from the comb between the china pencil marks. Periodically check your progress by looking at the bead. Stop when you can comfortably get your face to the centerline of the bore. Your stock will have a dished section in the comb. Blend the top of the comb over into a smooth curve. If you leave a sharp edge, it will come up during recoil and gouge your cheekbone. Rasp forward from the dished section to blend the contours of the stock. Again, if you leave the forward part of the dished section in place, it can strike your cheekbone during recoil. Sand the rasped area smooth and refinish.
Many shooters will have the opposite problem, that is the stock is too low, and they
