barrel tennons

[wdbailey]

okay you guys did a great job helping me bend my tang I was surprized that it bent so easily.
Now I am going to install my barrell tennons. It seems to me that these can only be made 1/8 inch tall and even then will extend to the ramrod channel leaving a slot in the ramrod groove. If the pins are 1/16 you only have the same amount for wiggle room. Is this correct or am I missing something here.

 

[paulvallandigham]

YOu need to drill test holes in the bottom of the barrel mortise to determine EXACTLY how much room you have between the barrel mortise, and the hole for your ramrod. Use the smallest drill bit size you can buy for this purpose, because all you are doing is using it as a depth gauge.

Then, cut your tenon to that dimension, so it doesn't extend down into the hole, and impede the movement of the rod. As much as its nice to not see that tenon sticking down through a notch into the ramrod groove, Its common for these tenon holes to punch through into the ramrod hole, or groove. You want the pin that goes through the tenon to be as close to the barrel as possible.

In fact, when setting up the tenon to be drilled, you mount it in the barrel's dovetail, and then use the barrel pressed against a fence on your bench drill, so that the outside of the bit rubs against the barrel as its drilling the hole through the tenon. That leaves the most wood between the bottom of your tenon and that ramrod hole. And, that is the way some gunmakers are able to keep those tenon notches from busting through to the ramrod hold and channel.

Remember, the forestock is NOT holding up the barrel; its the other way around. The Barrel is Hanging the forestock! The forestock's purpose is to protect the barrel from damage when the gun is used in the field and woods.

Half stocks became popular because they involved less work, a shorter piece of wood could be used, and the " half-rib" made first of oak, and later of metal, offered all the protection of the barrel that the long forestock did on Longrifles. More than one original longrifle stock showes evidence that the forestock has been damaged, cracked, or broken, and then repaired in some way. Some half- stock rifle stocks are clearly long stocks that were trimmed back after a break of the forestock.This is evident by the existance of dovetails in the bottom of the barrel for tenons, that have later been replaced by a Half-rib, removing the tenon, but leaving the dovetail in the barrel.

If you are working on a full stock, be prepared to sweat a lot over how thin that wood is getting, and how delicate it feels when the barrel is not attached to the stock. That is part of the challenge, when building longrifles, and the source of pride for the builder of a successful gun.

 

[wdbailey]

Thanks for the insight Paul! You mentioned putting the barrel against the fence of the drill press to drill the hole as close as possible to the barrel. That makes sense to me but how do you transfer the location of the hole to the outside of the stock when drilling it. I hope it's not too frustrating to deal with a rookie. I do appreciate your help.
Smoke eater aka Doug

 

[paulvallandigham]

YOu leave the barrel in the stock, CLamped in place, and use the same " fence " on the drill table to guide you. Of course, you need to mark the outside of the stock for the hole location. That is done with a ruler, and pencil, and then you check yourself using a divider sometimes. If you wrap masking tape on the top 3 flats of the barrel, you can draw a line, using a square, from the hole up onto the tape. Then with the barrel clamped to the stock, you can transfer that line to the outside of the stock, so that the hole is centered in the hole in the tenon.

Always drill smaller pilot holes in this kind of work. Remember that the hole in the tenon needs to be elongated some to allow the stock to expand and contract with changes in humidity during the eyar. That means that there is a little "fore and aft slop" allowed when you drill the holes through the tenon.

The critical dimension for these pin holes is to make sure that the holes line up vertically, under the barrel with the tenon. Using the barrel in the stock, and pushed up against the fence( you make a fence out of angle iron, or squared blocks of wood, clamped to the table) so that the drill actually rubs against the bottom flat of the barrel, and leaves a slight "groove " in the base of the tenon, you first drill the hole using a smaller drill bit size. I like to use something at least 1/2 the diameter of the finishing drill. This choice gives you some latitude to correct the drill location, if you are a little "off" before the final hole is drilled.

Measure 5 times, and drill once! :thumbsup:

 

[wdbailey]

Paul
Thanks so much for your help. It never ceases to amaze me how much of this stuff sounds easy till you actually start. We are fortunate to have so much experience on this site to help and protect us pilgrims.
Thanks again!
Doug Bailey

 

[Zonie]

Pauls method works fine for a straight barrel if you have the necessary drill press and a piece of material to use as a guide but it can get a person into trouble if the barrel is swamped.

I usually locate the pin hole by measuring from the top flat of the barrel to the bottom of the underlug with my dial calipers.
I repeat this measurement at each underlug and then measure the actual barrel flats to make sure I know what its thickness is at each location.
I then draw a little picture of the barrel and underlug and mark the dimensions.

On a swamped barrel I also measure the size of the octagon at the underlugs location and the dimension from the top flat of the barrel at that location to the bottom of the underlug.
I will repeat this measurement several times to make absolutely sure I have not transposed a number.
When I am sure I have the right dimensions I put them onto the barrel sketch for future reference.

In the case of a swamped barrel this measurement is necessary at each underlug and each barrel/underlug sketch is clearly identified.

Knowing the dimension to the bottom of the underlug I then subtract it from the barrel thickness at that location. I divide this answer in half and then add it to the barrel thickness.
This gives me the location for the pin as measured from the top flat.

I then set the dial caliper to read this dimension and lock it in place with the locking screw.

Replacing the barrel into the stock and lightly clamping it using small C clamps I then place a straight piece of steel across the top of the barrel at the underlug location. I don't clamp it there but it may help to keep it from moving if you do.

Using the "inside" measuring features of the Dial Caliper I place one of them on the underside of the piece of steel and using the other point I scribe a line on each side of the stocks wood. (It will be sanded off later).

Using a small combination square to determine squareness with the stocks sides I then draw a line down each side with a pencil. Where this line crosses the horizontal scribed lines that were made by the caliper shows where the pin hole should be drilled.

Here is where it gets interesting for those without a drill press or a little "drill jig" like the one I made.

If you don't have either of these you need to get a helper. His/her job will be to stand at your right or left and to tell you when you are holding the electric drill square with the world.
Then, keeping your fingers crossed and paying attention to keeping the drill straight to your line of sight and to the instructions of your helper you drill thru the stock at the mark you've made.
If you are careful everything will go great and the drill will hit the underlug right where it should.
Note: Sense you are drilling "blind" thru the underlug don't force the drill. Keep a medium pressure on it and let it do the work of making the hole. Now is not the time to break off that little drill bit.

Speaking of drill bits, I use a 5/64 diameter bit and a 5/64 diameter drill rod to make the barrel pin. My reason for this is I believe it is just too damn easy to break the smaller 1/16 inch drill bits off and the larger 5/64 diameter drill is longer. This longer length allows the drill to go all the way thru the stock from one side. (You really don't want to try to drill these pin holes from both sides. They almost never meet in the middle).

After drilling one hole thru, put a 5/64 pin thru it to keep the barrel from moving. Then repeat the whole thing at the remaining underlugs.

There are few tasks in building a rifle that can break you out in a cold sweat like drilling the underlug pin holes. :grin:

Oh, if you find that you have missed the underlug with your drill bit all is not lost. You will just end up with a fancier rifle than you though you would build.

Noting the location of the bad hole, mark a place on the side of the stock that would put the pin hole in the right place on the underlug.
Then replace the barrel, clamp it and redrill the hole in the right place. When you've got the hole in the right place and it is passing thru the underlug like it should then get out your catalog and pick out a nice suitable brass or German Silver inlay and order it. It will cover the "bad" hole nicely.
In my opinion, if you do have to install inlays to cover the bad holes you should order enough of them to be used at all of the pin holes even if they are in the right place. That way it will look like it was a planned design and not an after thought.

Have fun. :grin:

 

[jgunn286]

Zonie, Can you describe how to make a jig like the one you pictured? It looks like it would be a handy thing to have.

 

[chuck-ia]

I may have missed some of the suggestions, so sorry if I am repeating something. I am working on a A weight .36 southern rifle now, a couple weeks ago I dovetailed in the tennons, and drilled, with all the tennons in the barrel, barrel out of the stock, I figured the rear tennon would have to be drilled close to the barrel, or just touching the barrel, I set the barrel on my drill press and adjusted the fence, (angle iron) so the correct size drill bit allmost touched the barrel, I had the stock marked where the center of the tennon set in the stock, put the barrrel back in the stock, set a line level on the barrel (swamped) just behind the drill bit, leveled it, pushed the barrel tight against the fence and drilled through the stock and tennon, took the barrel back out of the stock, took a string and pushed it through the hole in the barrel tennon and tied a knot so it would not pull through the hole and streched the string to the front tennon, looked like with the string held close to the barrel on the front tennon the middle 2 tennons had plenty of metal on both sides of the string (up and down) set up the fence to just miss the barrel on the front tennon and put the barrel back in stock and repeated procedure as I did the back tennon, took it back out of the stock to check, took the string again and put through the back tennon hole and through the front tennon hole and streched it tight, yup, plenty of room for a hole through the middle 2 tennons. Put the barrel back in the stock and pinned it so the pins extended through the stock enough to lay a straight edge from the front pin to the back pin and drew a line from the top of the front pin to the top of the back pin, then did the same on the bottom of the pins, put it back on the drill press and leveled it with line level and drilled between the lines, actually came out pretty close on both sides of the stock. Hope this makes sense. flinch