Dunno about Ruger, but the Steyr Mannlicher hammer forged bbls have a swirling pattern of little flats on the outside of the barrel where the hammers beat the barrel down into the rifling mandrel. They look great and shoot like a laser.
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Be mentally deliberate but muscularly fast. Aim for just above the belt buckle Wyatt Earp
45 ACP: Give 'em a new navel! BigG
"It is error alone that needs government support; truth can stand by itself." Tom Jefferson, Notes on Virginia, 1785