One of my CF single-shot rifles, a Thompson/Center TCR-83, has a one-piece Leupold/Redfield/Burris scope mount - the ones that have opposing screws at the rear scope ring position as a rough windage adjustment.
I recently came across an emergency peep sight that fits the rear of the scope mount base, between the opposing windage screws, after the scope is removed for whatever reason.
It's a Buehler Little Blue Peep sight from the 1970's IIRC - and, since I thought there might be some interest here about the system, that I'd post about it.
(Sorry about the slightly out-of-focus pics)
![Image](http://s26.postimg.org/xkaw4dcl5/DSCN2070.jpg)
![Image](http://s26.postimg.org/e3q6huhh5/DSCN2068.jpg)
Methinks I'll need a bit higher front sight blade, and to remove the island rear bbl open sight, in order to zero it.
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