Quoted: I'd like to setup a MK12 Mod1 SPR type rifle and use it in daytime and night.  Is there anyway to adapt a PVS14/MUM to a setup like this?  Obviously I wouldn't expect it to perform as well as a dedicated night setup, but 200-300yards worth of engagement range would be very very handy at night.

Hi, keep in mind any time you use a day system in front of a NVD, you wil lose approx. 40% of the light while viewing through the NVD. The cheapest alternative is to use a universal type adapter as the one depicted below.


You will also notice you will have to move your day scope a bit forward to achieve the correct cheek weld and eye relief.

Below are some shots on what to expect at 3x, 6x and 9x.  These shots were taken with a Leupy 3.5-10LR. Range around 75 yards wih the set up depicted above. The last pic (9x) was taken using "Da torch" IR illuminator.




Your last option is to use a Universal Night Sight. (UNS)  www.omnitechpartners.com/osti/CutSheets/default.asp
These units go in the front of the day optic with virtually no loss of light nor focus.  Price for this item around 8K! Hope this helps.

Vic

The day scope is fine far forward and as for eye relief the PVS-14 rests very close to the objective of the day scope so no problems with this.  The only issue is your day scope zero changes of course from the normal day shooting position you have zeroed from.  What I do and most others is to have two seperate zeros at two different rail postions. Hence the reason so many new rails nowadays have numbered slot positions so you can place your optics at the same position each time.

Vic