While running pellet tests on some air pistols, I noticed that using a Beeman pellet seater (basically a 1/4" ball bearing on a rod) decreased group size. This would only be of interest to a "thumb seating" shooter.
I didn't persue it since it was a small increase, insignificant in an AP. I thought, though, it might have some merit for a rifle shooter with more stringent requirements.
Have fun!
Air accuracy
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