waterdogg:  The K-1 Pacific peep sight uses the hole for the magazine cut-off and attaches very securely.  It also fills the void in the receiver wall, left when the cut-off is removed.  This provides a smooth surface so that cartridges continue to feed without roughness.  The K-1 may require a slight notching of the stock for the sight to be moved to lowest elevation.  IMHO your Krag sporter may have an even more attractive appearance, if the forearm were shortened and the tip shaped like a Carbine stock, (this would require a wood plug to fill the exposed lightening channel).

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