A local gunsmith sets back the factory barrels on the 10/22 to achieve a bit less freebore, but does nothing else to the chamber. Claims the Ruger chamber is actually tapered. Does seem to improve accuracy. Of course any form of tight chamber in a .22 must take into account extraction. I've had problems with manual extraction in a 10/22 so modified, a loaded round sticking in the chamber when the extractor lets go before the round is extracted. It's a delicate balance.
Stupidity has its way, while its cousin, evil, runs rampant.
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