A chamber cast would determine if it is chambered for the .44XL or the .410. Also does it carry proof marks. Bore on a .410 is 10.4mm, while that of the .44XL would be around 10.8-10.9mm. "IF" marked as a gauge by the proof house a .410 (On Size) would be a 67.49 gauge.


Miller/TN
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