Re: PVS-14 Day Scope Adapter
The original design was / is called the "MonoLoc". Former SWAT Officer Richard Brough invented it. His contact information is here:
http://www.monoloc.com/contact/contact.htm
Richard is very approachable and helpful. I recommend that you call him and discuss your needs.
<span style="color: #FF0000"><span style="font-weight: bold">One important component of advice: Do not mount your PVS-14 on any rifle chambered for cartridge greater than .223 / 5.56x45mm. </span></span>
1. Since the PVS-14 goes behind the ocular lens of your day scope, the eye relief needed is only that of the PVS-14, not that of your day scope. You have to know that you will have the entire length of the PVS-14 extending behind the day scope. If your day scope has extended eye relief and your rifle stock has been set-up to accomodate the EER; and you're comfortable with your eye right up to your PVS-14 (for example, to where you can use the eye cup), you may not need any adjustment to the length of your rifle's buttstock. Otherwise, some shooters do feel more comfortable with several inches of extra spacer added to the overall "length of pull."
2. Rubber bushings are used on both ends of the adapter to grip onto the objective of the PVS-14 at one end, and to grip onto the ocular of your day scope at the opposite end. The MonoLoc uses levers to cinch down the metal sleeves that the bushings fit into, and to lock them down onto the scopes. The benefit of the lever system is that they lock and release quickly -- literally, at the flip of a lever. Other designs use thumbscrews which can be equally as secure, but is slower to tighten / loosen. The Monoloc lever system gives "a lot more leverage" and a very snug, secure fit when locked. Again, this can be achieved with thumbscrews, but with somewhat more time and effort.
3. With the release lever system used in the MonoLoc, the PVS-14 can be popped out of the adapter as fast as you can pull the lever open and pull back on the PVS-14, which is very fast. The thumbscrew fasteners work in a similar manner, you turn them until the metal sleeve + rubber bushing becomes sufficiently loose to let your PVS-14 move freely.
4. Performance of your night vision scope in conjuction with the day scope is something to consider. If your day scope has a high degree of light transmission and a larger exit pupil, you're going to realize better performance (or ability to 'resolve images') through your PVS-14. For most day scopes used in this kind of set-up, 4x is usually the upper limit of scope magnification before the image becomes too dark and grainy to be useful. The performance is, of course, not going to be as sharp and as clear as what can be obtained with clip-on NVDs such as PVS-22 and PVS-27.
Hope this helps.
IR-V