Inletting a Machined Stock

Many firms advertise stocks that are ’95 percent inletted, which sounds like it might be a snap to fit a barreled action. Wrong. It’s a fact that the so-called last 5 percent of inletting a barreled action can be the most trying and frustrating’not to mention the fact that the last 5 percent is where any mistakes made will show in the finished product. It’s been my experience that most gunsmiths who want to fit a barreled action to a machined stock have no intention of making a career out of it.

Some are professionals, of course, but many are amateurs who simply want to learn more about inletting and want to try to expand their skills on a onetime project. I’ll try to help both the amateur and the pro here, and try to pass on a few "tricks of the trade" from someone (yours truly) who specializes in stock work and inletting. When the machined stock arrives, a careful examination of it is in order. Look for flaws in the wood such as bark inclusions, drying checks, and the like.

Ascertain if they are repairable with epoxy. Never use white glue, yellow glue, or wood filler on a custom stock. It will show, and it will look ugly! If the damage is more than you can deal with, call the wood turner and explain the situation. Most will exchange the stock unless you have tampered with it. Now let’s get started. Do a bit of dry fitting to calculate how much work is involved.

Most machine-carved stocks are machine inletted as well, so a certain amount of wood must be removed in order to fit the barreled action. Don’t be in a rush. Plan your attack, and go slowly. I don’t have any particular carving or woodworking skill that allows me to stand out except one’and that’s patience. So take your time. If the barreled action has a onepiece bottom metal unit (trigger guard, floor plate assembly), most of the experts call for inletting this first.

I agree with that approach, as it helps you to properly align the "top metal" (barrel and receiver) later. If you have a barreled action with a two-piece bottom metal, you have no choice but to inlet the top metal first. Pre-64 Winchester 70s are in this category. It will be most helpful to acquire a few specialized tools to make your task easier. Inletting pins area must for me, as are T-handles. These can be purchased from Brownells or other gun tool suppliers.

The inletting pins are useful from the beginning in aligning the barreled action. The T-handles are useful during the later stages of inletting, as they allow you to pull the bottom metal and top metal together quickly and easily. You can, of course, use the forward and rear tang screws, but as many times as you will have to "try and fit" the parts, they’re bound to get damaged. We’ll begin here by fitting the bottom metal.

First, insert the T-handles in the forward and rear tangs and fit them into the screw holes in the machined stock. In all likelihood, the bottom metal will be a bit larger than the machined inletting. Take a sharp

scribe and carefully scribe an outline of the tangs. This is your starting point. Remove the bottom metal and begin to cut away the excess wood, staying inside the lines you just scribed. Use a medium-coarse burr in your Dremel tool and begin by removing the excess wood from the curved ends of the tang recesses. Then coat the bottom metal with a marking agent’either lipstick or one of the commercial spotting agents’and refit the bottom metal using the T-handles for correct alignment.

Give the bottom metal a light tap with a plastic or rawhide hammer. This tap will impart marking agent to the wood. Remove the bottom metal and note where the spotting agent has left marks. These are high spots and indicate where wood must be removed. Once again, pare away the excess wood. Repeat several times until the bottom metal begins to slip into place about three-quarters of the way in. Now it’s time to work with the "top metal" (the barreled receiver).

If the machined stock has a "starter" barrel channel, you won’t be able to get much of an impression using the spotting agent. Here’s what I do: Turn the barreled receiver upside down and place it on the stock, aligning it so that it’s centered. Then take a sharp scribe and outline the barrel, being careful to stay inside of the barrel contour. Remove the barreled receiver and use a sharp pencil to trace the scribe marks to make them more visible.

Now go to the drill press and, using appropriately sized Forstner bits, hog out the barrel channel from the recoil-lug area to a half-inch short of the end of the forend tip, being careful to stay inside of the scribed pencil mark. This last half inch will be carefully opened up using rat-tail rasps and chisels so as to not have a square bottom visible once the barreled receiver is fully fitted. Use Forstner bits to open up the recoil-lug area.

The barreled receiver should now drop partially into place in the stock. If you haven’t done so already, remove all the extraneous parts from the receiver’t he trigger assembly, bolt-stop assembly, and the like. These parts will be inletted after, and only after, the barreled receiver is fully inletted and bedded. With spotting agent liberally coat-

ing the barrel and receiver, begin paring away the excess wood using the stock pins to align the parts. Take it slow and easy. Remember you can’t replace wood that has been removed. Once the barreled receiver is approximately halfway inletted into place, use the T-handles to align more precisely, and slowly draw the bottom metal and top metal together. Now’s the time to complete the fitting of the bottom metal by the "try and fit" method. Make as many fittings as necessary to achieve a perfect fit.

The fit should be tight, but not so tight that the part is difficult to remove. Remember, as the part becomes fully inletted, the marking agent will appear as it slides down into the inletting. Be careful to remove these marks or you will likely open the inletting too much, ending up with a case of "gaposis." The same thing applies to inletting the barreled receiver. The top metal should be inletted to one-half of the barrel diameter.

Use a pencil to scribe the sides of the barrel to the tip of the forend to check your progress. Then go a fraction of an inch deeper so you will have a bit of wood to play with when you complete your finish sanding. Tap the barreled receiver with a plastic or rawhide hammer to reinforce the marks left by the marking agent just as you did on the bottom metal. Use chisels, a Dremel tool, and abrasive paper wrapped around various-sized dowels to remove the high spots left by the marking agent.

Take your time and every so often step away from the project to take a look at your progress. When you’re satisfied that the barreled action is fully inletted’both the top and bottom metal’you can begin preparation for bedding the barreled action with epoxy. It’s important to remember that the epoxy is not to be used to fill in mistakes but to reinforce and waterproof the wood. I’m convinced that the best way to get a perfect bedding job is to do it in stages.

First, I do the recoil lug area and rear tang, then the barrel channel, and finally the receiver. Coat the entire barreled receiver with release agent or wax, being certain that every part is covered. I use children’s modeling clay to fill in any opening in the

metal to prevent the epoxy from flowing into these areas, which could make it difficult or impossible to separate the wood from the metal. If the cartridge being used is larger and more powerful than the .30-06, I always reinforce the previously hogged-out recoil area with "atomized" aluminum. For Magnum cartridges, I use recoil cross bolts with plugs to cover the holes in the sides of the stock. You can’t be too careful.

Now that we’re ready for bedding, here’s how I do it: The previously hogged-out area of the recoil lug and rear tang are first. Drill out the reartang screw hole from the top with a bit of about 3/8-inch or so. Go down about halfway. You don’t want to drill that hole all the way through, because you want the smaller, lower portion of the hole as a guide for the Thandle. Also, too large a hole will allow the epoxy to run out before it sets.

Use generous portions of modeling clay in those places where you don’t want epoxy, such as the triggerassembly inlet and magazine cutout behind the recoil lug. If you’re working with a Magnum caliber, mix up enough Acraglas (from Brownells) to fill in the recoil-lug area, with a little left over for the upper rear tang. In this case, I’ll mix in a generous portion of atomized aluminum. What that does is essentially form a solid block of aluminum when it cures.

I also use a small amount of black dye to color the mixture. For any standard cartridge up to .30-06, I use Acraglas Gel, because it’s easier to work with due to its thicker consistency. No additives are necessary with Acraglas Gel except coloring. With the stock set firmly in your vise, pour the epoxy mixture into the recoil-lug opening and the rear-tang inlet, and carefully set the top metal in place. Insert the T-handles through their respective openings and slowly tighten up the forward handle.

Don’t tighten the rear-tang T-handle, as it’s used to keep the epoxy from running out. We want the action/receiver to settle in place without any stress on it. This will become clear as we proceed with the second step. Once you’re satisfied that the forward T-handle is tight, wipe away any excess epoxy that has oozed out and set the entire assembly aside for 24 hours to properly cure. The next day, carefully remove the barreled receiver from the stock and clean up any excess epoxy. Examine your work.

If you followed the instructions carefully, the aluminum/ epoxy mixture should be hard and without any major voids. Now on to step two. Recoat the barreled receiver and bottom metal with release agent to prepare them for additional epoxy. Also, don’t forget to do the same with both T-handles. Drill out the remainder of the reartang screw hole from the bottom as well as the forward tang with the same 3/8-inch drill you used before.

What we’re going to wind up with is a variation of the pillar-bedding system, as the epoxy will form a solid pillar promoting accuracy. Coat both lower-tang inlets with Acraglas Gel and carefully set the bottom metal in place. Use masking (continued on page 21)

tape to hold it in place and then turn the stock right side up. Generously coat the barrel channel with the epoxy gel and carefully set the top metal in place. This time, use both T-handles to tighten the top metal and bottom metal in place, using first one and then the other. Since the recoil-lug area and rear tang have been previously epoxy bedded, the top metal should slide precisely into position without too much trouble. Be certain the barrel is fully seated to the end of the forend to get an exact fit.

Wipe off any excess epoxy to make removal of the metal easier. Wait 24 hours and then remove the metal. I prefer to remove the bottom metal first followed by the top metal. Step three in bedding is to bed the sides of the receiver. Some experts think this step is not necessary, as the amount of bedding compound used is slight. I like to do it anyway, since it gives the bedding a finished look and also waterproofs the receiver area.

Coat the receiver with release agent and then mix up the Acraglas Gel as before, and apply it to the sides of the receiver and also to the wood. Fit the top metal into the inletting and tighten as before using the T-handles. When the gel sets, the bedding job is complete except for the cleanup. Reassemble the trigger and boltstop assemblies to the action and inlet them into the stock.

If the machining job was well done, it’s likely all you’ll have to do is to cut grooves for the various pins in the trigger assembly. On Mauser actions, the bolt-stop assembly must also be fitted to clear the wood without a large gap. And let’s not forget the bolt notch. This is also inletted into the stock by the "try and fit" method. I prefer the Dremel tool with various-sized burrs for this task.

Be certain the rear of the bolt handle clears the wood or it will chip wood out of the notch if there is the slightest setback upon firing. Finally, reassemble the rifle and check that all is in working order. If you followed instructions carefully, you’ll find you have a near-perfect result. If you discover voids in the epoxy which you consider excessive, you might want to "paint" on a coat of Acraglas epoxy. A paint coat implies what it is’epoxy spread in a thin layer to fill in any voids. I