An Improved Rifle Rack for Offhand Stands
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As an ex-Army competitive shooter who is now a volunteer coach for a large junior program teaching Olympic small-bore, I’m constantly looking for ways to reduce the distractions and inefficiencies of match preparation, and getting the rifle off the ground to speed buttplate and sight adjustments is an excellent example. While there is at least one commercial model of these “antler†rifle racks available, it is unpopular with our advanced shooters and coaches because its design allows the rifle to spill out of the rack should the arm screws come loose, and is considered too flimsy in construction, making the offhand stand easy to tip over and easy to damage the stand’s shaft by over-tightening the set screws. As a boatbuilder by training who often has to fabricate custom hardware, I designed and made another that’s a bit heavier and shorter, grips the much stand better, and is totally spill-proof. It’s been surprisingly well-received, so I prepared this tutorial on making one in a modestly-equipped home shop, as there are far too many operations required to make this a profitable venture for any but fully-equipped commercial machine shops with forging and casting capabilities.
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To improve gripping the offhand stand’s easily-dented aluminum shaft, I increased the surface area in contact by using thicker stock for the base, and shown are 1â€-thick aluminum plate scrap acquired locally. Three-quarter inch thick would also work well. Also shown are the remaining materials necessary to make these - half-inch aluminum rod stock, thick-walled latex surgical tubing of half-inch inside diameter for padding, and a handful of assorted-length ¼ X 20 thumb screws through one-inch. (Aluminum doesn’t like fine threads.) Alaska Copper in Seattle or McMaster Carr in Baltimore can supply new plate, Tacoma Screw or Home Depot the rods and hardware, and eBay has a good selection of latex tubing. Local scrap yards can also be excellent sources of materials, especially for the heavier stock that can be expensive to buy new and ship. Finding one near a shipyard or other major manufacturer can be very rewarding, even if you have to do business via telephone and UPS.
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I cut the plate into rectangles of 2 X 5 3/8 inches on a power band saw with a bimetal blade. You could also cut the stock by hand using a hack saw or take it to your local metal fabricator and pay to have it cut to your specifications. Length isn’t critical plus or minus a half inch – I selected 5 3/8 based on the capacity of my drill press. Lubrication isn’t absolutely necessary when cutting soft aluminum, but can speed things up and extend blade life.
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I clean up the bandsaw marks by taking multiple, 1/32†trimming crosscuts using the miter gage and a carbide-tipped blade in my table saw. Care is required, as are adequate safety glasses. Don’t expose any more blade above the saw table than necessary, because like in any table saw work, it’s only the carbide teeth that do the cutting. Feed the workpiece sufficiently fast or misaligned so that the stock you are cutting comes in contact with the steel saw plate instead of the teeth, and the workpiece will be thrown with great force. And don’t even think about making this crosscut soley on the table saw, as you can’t feed material this hard into a table saw by hand with sufficient consistency to avoid it being thrown.
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Next, I lay out my stock for drilling for the arms, allowing a quarter - inch thickness remaining in the walls so they can take holes and threads sufficiently strong for set screws to hold without stripping.
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I drill the half-inch holes for the arms in three incremental passes of increasing size, flipping the workpiece to drill from both ends. This is based on the depth and power limitations of my radial-arm woodworker’s drill press, but incremental drilling of long holes generally allows for a more accurate hole, as the larger drill sizes act as reamers, following the original pilot hole.
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I’m very careful to use low speeds and not to take more bite with the drill bit than the bit’s flutes will clear the waste from, plus I clean the chips from the workpiece and flutes as I go. This usually means quarter-inch bites to begin with and eighth-inch bites as the hole deepens, covering and filling the clearance flutes with chips. In this job, as the arms are inserted into the base from each end, perfectly-concentric holes aren’t absolutely necessary.
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After drilling for the arms, I center-punch dead center of my base stock for the 1 1/8†shaft hole necessary to fit the offhand stand, a hole that will be drilled with the arms mounted.
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Next, I begin the process of bending the half-inch aluminum arms using an oxy-acetylene torch. This requires some practice, as aluminum’s temperature increment between being sufficiently hot for easy bending and crumbling from too much heat is small compared to bronze, brass or steel (which are adequate but significantly heavier alternatives for those who have trouble getting the hang of aluminum.) The technique here is to use an acetylene-rich flame to smoke the rod, followed by adding oxygen so as to heat the rod slowly with a neutral flame to the point where the flame burns off the soot. By moving the flame gradually up and down the rod to clean it, the rod becomes uniformly heated to the correct bending temperature when all the soot is removed. For those without an acetylene setup, MAPP (or probably even propane) gas can also be used if you first soot the rod using an alcohol lamp burning mineral spirits like in fitting the swamped barrel during the antique stock repair shown below:
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Continued...
