I'll try to resolve some questions, except for the shooting - as I'm not going to be able to get to my club for a few days.
The forward portion of the inserts are bored to .22 cal & rifled - and result in a barrel only slightly shorter than the 1" bbl on a NAA Mini revolver.
So, no bounce - the bullets are not thrown downbore.
Instead, think: Shooting a .22 down the center of a 4" long piece of sewer pipe.
They don't have any O-rings ( or onion rings, either
![Wink ;)](./images/smilies/icon_wink.gif)
) - but are a nice/snug fit in the chambers.
So snug, that when I want to go back to shooting .45 Colt cartridges, I have to start the inserts out of each chamber by slightly offsetting it, and tapping the insert with the EJ rod.
There's NO alignment effort needed, with the revolver's firing pin, since (if you'll look carefully) the .22 chamber is reamed where, no matter how the insert is oriented, a portion of a .22's rim will always lie central in the .45 chamber.
That said, there's not much orienting to be done, since the EJ rod must be able to eject the rimfire casing, leaving the insert chambered.
The installation instructions say to hold the EJ rod all the way to the rear while chambering the insert, to ensure it's properly positioned.
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