First, measure the bore(s) of the gun. Depending on the age, and the maker, the diameter can vary widely. Use a caliper to measure the bore.
Nominally, a 14 gauge bore should be .693" in diameter. ( That is often referred to as a .69 caliber gun.)
RB loads can be as follows: Try
2 1/2 drams of 2Fg powder( 69 grains) under a one oz. approx. RB., Then try 2 3/4 drams ( 76 grains) of 2Fg, and then go up to 3 1/8 drams( 86 grains) of 2Fg for the heavy load. I think you will find that 70-75 grains of 2Fg is more than enough powder with that heavy ball for any deer.
Track of the Wolf sells cast balls in .672, .675, and .678" diameters that should fit a 14 gauge barrel if its close to the nominal diameter. You want a ball with a diameter at least .020" smaller in diameter for use in a smoothbore gun.
http://www.trackofthewolf.com/Categories/TableList.aspx?catID=2&subID=25&styleID=58&PageSize
Use a .015-.020" thick Mattress ticking, #40 pocket drill, or denim cloth patch around the ball. Wash the fabric to get rid of a product called "sizing" that the manufacturer puts in the cloth to make it pack tighter for shipping. Sizing is similar to starch. Get it out of the cloth, so the cloth will absorb your lube completely.
Expect all fabrics to "compress" at least a 1/3 of their thickness in the barrel. When the fabric is properly lubed, it will also " stretch a bit, to make a tight fit around the ball. The fabric patch provides the gas seal in the barrel, protecting the soft lead ball from gas cutting( bad for accuracy) and insuring consistent MV from shot to shot. That promotes accuracy, too.
Lube the patch with some vegetable based oil compound.( Don't used petroleum based oils in the barrel. They are fine for lubing action parts, but they produce gummy "tars" in the bore, as the heat of burning black powder is not enough to burn these oils completely.) Under " articles" at the top of this forum's index page, you will find a recipe for Stumpy's moose snot patch lube. Use it. Or "borrow " some lube from your friend.
Dutch Schoultz promotes the use of a "Dry" path formula, for patch lube, where he mixes oil with water, in a ration of 1 part oil to 5-7 parts water( depends again on what your gun likes) and then spreads the mix on strips of fabric, and lets the water evaporate in the sun, or in an oven on low heat. This allows the oil to penetrate the fabric threads completely, to give consistency to the amount of lube in each patch, but leaves the surface of the fabric dryer to the touch, so you don't get oil all over yourself.
http://www.blackpowderrifleaccuracy.com/
Only testing each component, one at a time, will get you the accuracy you want with that smoothbore. Buy Dutch's Blackpowderrifleaccuracysystem for $19.95. It will take you through the steps needed to zero a gun and find an accurate load. Its the best $20.00 you can spend on your education about Traditional MLers.
Yes, go to your local fabric store with a micrometer, and actually measure the thickness of the cloth, before buying some samples to try. Cltoh is usually sold by the yard, but if you ask nicely, they may sell you a strip that is only 1 foot wide, as a " Sample.".
It won't take much testing at the muzzle of your gun to find out if a patch/ball diameter combination is too tight. Use a strip of the cloth, and push the ball into the muzzle behind the fabric, with your thumb. If you can't push the ball in with your thumb, try a smaller diameter ball, or thinner patch material. Mark each sample cloth somehow to tell you what its thickness IS. It will save you from having to measure them again, so you can go back to the store and buy several yards of the correct material to make lots of patches. :thumbsup: