I don't rightly Know. I have never used such bolt-mounted sights.

The well machined sight featured in the DoubleGunShop Boards may be a one of a kind custom or prototype sight. It probably works well. Maybe some of the many surfaces assist a snug alignment. (It appears part of the right side-plate contacts the receiver).

I would like to see the whole rifle.
IMHO - That rare rear-sight sits quite high and would require a rather tall front-sight. Also, probably a high comb on the stock.

Both it and the Rice sight merely have a simple 'peep' hole and lack the refinement of screw-in apertures. The likely intent of both sights was 'Woodland Hunting'. The systems were probably quite adequate for short range hunting in cover, 25 to 125 yards.

I have never shot a Krag with the Leroy Rice sight.
Attached are photos of the Rice instructions, which address eliminating 'bolt play'.

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