I went to the club on Sunday and tried the 'bare ball and wads' approach with the harpers ferry. The first few were low and right - the musket seem to shoot all loads down there - so I aimed high left and the next three were in a group about 3" across and in the black. Woohoo, thinks I, i've cracked it. Nope. The last 4 shots were good for height and reasonable for group but right on the left hand edge of the paper, so with the same POA the POI was probably 18" left of the three shots before. At that point it started to rain so I said some rude words and went home!

Any thoughts as to why the POI would shift so drastically?

Thanks in advance, Jamie

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