The bores in my Dickinson are nowhere near .410. In fact, they measure .399" right and .398" left. So, just using a caliper to measure the muzzle I.D., then subtracting that from .410" won't tell you anything (unless your bores really are .410"). My other .410s are all over the place in bore diameters. The Yildiz is .400" and .399", and the Verona is .410" and .410". It seems the Turks aren't satisfied with building a "little gun", they want them to have undersized bores. If there was ever a gun that would be helped by overboring it would be the .410, IMO.

SRH

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