Form my experience and in bowling literature, there seem to be 2 "schools" for this conversion which also are applicable to the 7-10 - but these are justa academic, I think.
Strategy #1:
The "conservative" direct version: try to make a very light outside hit on the preferred side of your choice. For the 4-6 this means either aiming for the 7 or 10 pin, hoping that the slight hit creates just enough sideways movement or tumbling to have the pin fall over in a 90° angle and take out the other pin. Medium speed recommended.
For the 7-10 this would mean a well-placed shot into the gutter in the pin deck area, with more speed for the longer journey of the target pin across the deck or making it bounce off the back wall back into the pit to take out the other corner pin.
Strategy #2:
The indirect "rebound" version: This time, aim for an inside side hit an the pin of your choice. Higher speed for more pin action. Idea is to have one of the pins slam sideways into the pit wall and make it tumble back onto the deck, taking out the one still standing. For the 4-6, this needs a lot of energy. For the 7-10 I think that this would be more effectice than the outside hit method #1, but I haven't seen anyone making both, either accidently or with a certain plot for the shot.
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DizzyFugu --- Reporting from Germany
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