Something most people are unaware of.
I have two identical rifles but they are not.
I have been told not to wear the same shoes every day or my feet would soon cease to resemble feet. Sitting in my bedroom this morning, which resembles a small terrorist after action scene, I noticed I had nine pairs of shoes sized nine and a half D. Seven appear to be identical and were probably made in China to American standards. They must all be alike. Right? Well they should, but some are almost too tight fitting to wear and others are much more roomy and comfortable. What could possibly be the difference? They were all made to “be in the neighborhood of 9.5 D” but there is that obvious variation. That slight variation exists in everything that is manufactured and is of particular importance in all rifles including the wonderful muzzleloaders.
Charley has a gun barrel just like yours. If you load a patched ball using one of his balls cast from a single ball mold using his patching material and carefully calculated lubrication, the two rifles may shoot exactly the same, but often in this experiment may shoot a little bit different because of tolerances allowed in the making of the two barrels. His barrel may be a very slight bit bigger than yours or vice versa. Now if we change the lead ball to one that came labeled to be the same size as Charley’s we now have added another variable to increase the possible difference. Charley says his shooting patch material is .015 when measured the correct way with a micrometer and so does yours, and here can be a much greater variable because Charley’s patch material, when measured using a compressed method, will shrink to .0135 when crushed between ball and bore and yours will crush even further to .095. So you and Charley think you are loading and firing the same load in two identical rifles and getting surprisingly different results. Maybe now you can see how this happens and how Charley is getting better results doing exactly the same thing you are. or so you think. This is where the micrometer comes in to play.
To shoot well you must try to eliminate those variables caused by the teetotal sum of all those variations. Use balls all cast from the same mold. Use patching that fits exactly to form a perfect seal around the ball and keep all other elements exactly the same and you should have consistent satisfactory results.
Sometimes you can correct a small variation by using a “shim”. I used cigarette paper which is very thin placed between ball and the patch you are currently using to add that very small extra thickness to see if it has a positive effect. If not, then try two sheets of this thin paper to increase the total thickness even further. In my experiment I found that three sheets of this paper made a noticeable and positive difference, so off I went to the fabric store. micrometer in hand, to find an all cotton denim whose compressed measurement is the same as that of my old patch material plus the three sheets of thin paper. It was surprising to me how such a slight difference could have such a big effect on target.
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