Went to the range here today to shoot the Gibbs.450 and the Manton 10bore.

No rest. Shooting 50 m completely off hand. I tested some different shooting styles in regards to see if holding the double differently changes the grouping. And it does.

1st grouping(circle 1) here on target the shots pulls to the left. The second grouping I change position on the shouldering and the grouping tighten and moved.
The hole in top is a 10bore for comparison.
The disc is an anglegrinder disc.

I changed the last shooting by placing the rifle a little more center to the core.