Tips & Tools with Fred Stutzenberger – Part 10B
Tips & Tools #10 Part B
If you have not gotten around to choosing the method of barrel-to-stock attachment, here is a summary of some of the tenons (also called underlugs or tabs) that I have used in the past (Fig.1). Tenons a, b and e are of the dovetail type (e shows how I run the a-type off en masse on the milling machine in strips). For those, you must cut a dovetail in the bottom flat. C is a loop with feet that are staked into carefully drilled holes. D is shown in greater detail in Fig. 2 (I generally use the d-type for its versatility and strength, easy installation if you are friends with a milling machine). F is a stronger version of d; the tenon is left full thickness and is staked into the flat via a groove cut with a 60° dovetail cutter. The d-type tenon can be filed to shape in a few minutes if you do not have access to a milling machine.
You know by now that I like D best of all. It has a foot to be staked all the way around its perimeter. It is very strong and receptive to keys because it provides plenty of room for slotting (Fig. 3) to allow for differential expansion/contraction. If you are pinning a thick-walled barrel, you may be tempted to merely mill a little indent into the bottom of the barrel (Fig. 4). This method was suggested in Recreating the American Longrifle (William Buchele et al., 1983). This is a fine book, but don’t use this method of barrel attachment. It is very hard to slot the pinhole; if you don’t slot it, and the wood shrinks while the barrel expands in a heated area, you will find (as I did) that the pin is locked in, creating a real chore to remove.
I use 1/16” diameter oil-hardening drill rod for my pins. A three-foot length costs less than a dollar from Enco Manufacturing. It can be hardened and tempered, but I have found that it is sturdy enough as it comes from Enco. If you are building a rifle that requires keys (as most halfstock rifles do), you can buy them (see suppliers’ list) or make them yourself by first milling the blank and then shaping the head by peening and filing. Fig. 5 illustrates a purchased cast key and two stages of a homemade key. Making a key is pretty simple on a milling machine, but is a chore to make by hand.
The positioning of pins or keys is dependent on the length of barrel and type of rifle. On a fullstock, I position my rear pin eight inches ahead of the breech and the front pin about one inch back of the muzzle cap. Then the other one (or two on long barrels) are placed equidistant between the front and back positions. On a halfstock, I use two keys, one about seven inches forward of the breech and the other about two inches back from the fore end cap to stay out of the way of the entry thimble. Look at some old rifles to see how they did it and use enough forethought to consider where your ramrod thimbles will be placed later.
Now for the actual pinning or keying. I once saw Hershel House drill the barrel pinholes freehand with a hand drill, but mere mortals such as I require a bit more precision by using a drill press.
- Clamp a piece of angle iron or other stop on the press table
- Clamp the barrel firmly to the stop in position so that you can bring the drill bit down squarely to the middle of the tenon. That shows you where the bit will drill through the tenon when assembled in the stock.
- Mark the relative position of barrel and stop on both by making index marks.
- Clamp the barrel firmly in its channel and extend the barrel index mark across the side of the stock. You will be drilling through that line on the stock, the tenon and out the other side.
- Clamp the assembly firmly to the stop, making sure it is square to the direction of drilling in all three planes and all index marks line up.
- When drilling for the pin closest to the muzzle, you will need a mechanical support or an assistant to hold up the butt end of the rifle from cantilevering the rifle off the table.
- Slide the bit up into the chuck as far as possible to stabilize the point.
- Start the drill press running and bring the bit down into the stock a bit to mark the desired location for drilling.
- Raise the quill back up and slide the bit out of the chuck far enough to allow it to drill all the way through the stock.
- Drill all the way through, raising the bit frequently to clear chips.
If you are installing keys, drill a series of holes and connect them with a needle file to make a nice even slot as shown in Fig. 3. You can also use a small end mill or a Dremel Tool to remove wood, but be careful. Tools that remove material rapidly also rapidly make mistakes. To remove the wood from both sides of the slot in the stock, you can grind a little saw from a piece of hacksaw blade that can reach in from both sides and carefully remove the wood between the holes. Remember that if you carelessly remove too much wood from the upper side of the slot, the key will not hold the barrel firmly down in its channel.
This part essentially completes directions dealing with barrels. For more details on barrels, check out the 8-part series, Essentials of Barrelmaking in Muzzle Blasts that appeared in 2000. See below:
| Muzzle Blasts (the magazine of the National Muzzleloading Rifle Association)
|Essentials of Barrelmaking||Part I||March 2000||Page 9|
|Essentials of Barrelmaking||Part II||Aprril 2000||Page 11|
|Essentials of Barrelmaking||Part III||May 2000||Page 13|
|Essentials of Barrelmaking||Part IV||June 2000||Page 9|
|Essentials of Barrelmaking||Part V||July 2000||Page 7|
|Essentials of Barrelmaking||Part VI||August 2000||Page 9|
|Essentials of Barrelmaking||Part VII||September 2000||Page 11|
|Essentials of Barrelmaking||Part VIII||October 2000||Page 13|
ENCO, 1-800-873-3626, for drill rod and mild steel sheet suitable for a variety of muzzleloading parts.
Track of the Wolf (trackofthewolf.com) has a wide variety of barrel keys and pin stock.