indeed a slip in insert that can be removed later....would be really interesting to load up a few rounds of 00buckshot and see what it patterns like without wad and do same with birdshot....would be much more fun for bunny outside the back door than boring old silenced .22lr even if the 22lr is unique in its own right. no need for load them hot at all..black powder ones would be ideal,you already got the cleanup sorted.
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