Just to see what all the fuss is about, I knocked one up out of Delrin this afternoon.

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Whether it makes a difference I have yet to find out

But you can feel the pellet going into the rifling as you push the breech home. On the Steyr, there is only about 35mm gap when the breech is open, so it is easier to push the probe gently with the breech, unless you have tiny little fingers.