Measure the exact bore diameter of your 14 ga. shotgun with calipers. Then make a mandrill( a round piece of wood dowel, or a piece of metal rod or tubing, if you can find something the right size) that will be at least .030" smaller then the bore diameter. This will be used to form the shotcups.
Now, form a cylinder using cardstock- like 3 x 5 index cards. Glue the two ends together. When the glue is dried, fold over one end of the tube and glue it down to close the cylinder to form the cup.( If you have ever made up coin rolls using the paper coin wrappers you can get at a bank, you have an idea how to make these folds.) You don't want corners sticking out!
I have been using 3M " Post-it" notes paper, because it already has a glue strip on one edge. This is not as HC as you indicate you want to go, however. I wrap the paper around the mandrill twice, and then seal with the glue strip. To seal the folded end, I dip the folds into hot wax, and then tamp the folds on wax paper until the wax cools. It seals the end of the cup well, and provides a bit of lube to the cups, which melts in the barrel as the load is being fired.
I load the gun with powder, OP Wad, then the shotcup, then an OS card to keep the shot in the cup. I am going to change my field practice and begin using ONLY OS Cards for all this, and use up my existing OP wads on the range. 3-4 OS cards can replace the OP wad, and 2 OS cards will hold the shot in the barrel.
Remove the cup from the mandrill, and make another. Test the cup to make sure it slides easily down your muzzle, but don't push it down until you have powder in the barrel. If its tight, reduce the size of your mandrill again, until the paper cup you make does slide down the muzzle of your gun.
By folding over the ends of the cylinder and glueing them on the end of your mandrill, you have that internal support for the cup to maintain its shape. You can even tamp the end of the mandrill over the folds, on a flat surface to flatten the folds better, and then hold the folds against something solid as the glue dries. Just put some wax paper between the glue and the surface. You might be better served if you dip the working end of the mandrill into hot wax, too. That way, if there is any glue that gets through the folds, you won't glue the cardstock to your mandrill.
Nominally, your 14 gauge should have a bore diameter of .693.
I suggest using a commercially available 5/8" dowel for the mandrill. That comes in at .625, compared to the .693 bore diameter, or 11/16", but That is less hassle to work with then trying to create a closer fitting mandrill. You can always increase the diameter of the 5/8" dowel by wrapping tape over it.
How deep do the cups have to be? That all depends on how much shot you intend to fire out of your gun. If you are shooting strictly lead shot, then loads up to 1 1/8 oz. are about as high as you should expect to go.
See Bob Spenser's Black Powder Notebook, and the V.M. Starr article for loads for the 14 gauge.
http://members.aye.net/~bspen/starr.html
If the cup is at least 2 inches long, it will fit any amount of shot you intend to pour in it, and give you extra paper to tear( or cut) off at the muzzle.
When you settle on a standard charge, you can trim the paper cups to size at home, to speed up loading at the range or field. If you can find a 14 gauge plastic shotcup, you could simply measure the height? or depth of the cup to determine how much length your cup will need.
When I first began to make these for my 12 gauge, I poured shot into that first test cup, just to see how long the tube would need to be. I already knew my favorite load for the gun, so establishing the length of the cup was not difficult. I then cut my paper to create that length of a cup.
I like to support the bottom of my cups by putting a thin fiber wad( 1/16") in the bottom of the cup.This provides a even, flat surface behind the shot to push the shot down the barrel, and out the muzzle. Releasing the shot at the muzzle tends to help decrease the size of patterns, from my experiments.
If you go with that 5/8" mandrill, buy some OP wads made for the .20 gauge guns, and use them inside the cups. You could also use a couple of OS cards, instead of the fiber wad, to perform the same function.
The idea is not to increase the weight of the cup, because that simply produces another projectile that will follow the shot down range, and even blow the pattern if it bumps the shot after the shot separates from the cup. You want the cup to be strong enough to stay together before loading shot into it in the barrel, but light enough to separate from the shot on leaving the barrel and fall away from the line of fire.
The real work will be deciding how many, and how deep you will cut slits in the cup, to create petals so that they will fold back when the cup hits the air and release the shot. My own testing indicates that the shorter the slits, the tighter the patterns. I just don't know how tight I can get the cup to make the pattern, as I ran out of daylight the day I was able to test my cups. I have since modified how I make the cups, to make them lighter. You do need the " air brake " effect that petals give to the cup to provide uniform separation of the cups from the shot. If you shoot the cups without slits, you are like to get a single hole in the paper at 25 yards, about the diameter of your barrel. ( Been there, done that! :redface: :shocked2: )
If you use the OS cards, poke an off-center hole in each of them with an awl, to let air through. That air separates the cards from each other, and makes the cards very unstable in the air, causing them to quickly fall down out of the line of shot when they leave the muzzle. If you use the OS cards instead of an OP wad, just align the cards so that none of the holes line up with each other. That way you get the seal you need to keep the gases behind the wads, and the wads separate quickly and fall away in the air.
A lot of us are experimenting with paper shot cups and trying to improve the patterns we get. If you have some success with your cups, please let us know what that is and how you are doing it. :thumbsup: :hatsoff: