It is likely that the chambers were cut this way on purpose, to prevent the cylinder from locking up like the S&W .22 Jets did.
Revolvers don't like bottle necks and sharp shoulders. The cases jam the cylinder and you can't shoot it and you can't open it.
With the HMR, if the shoulder and neck disappear when fired, it's no problem, cuz you can't reload it, so who cares what the empties look like.
Let us know what Taurus says...
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