26 Mar

>ATN PS-40 Generation 4 Night Vision Device with BAM mount on EGW HD Base on Savage 10 FCP McMillan .308 Winchester

Steven K. Ledin,


My Savage 10 FCP McMillan has a new top end on it. It’s the ATN PS-40. After decades of professional gunstuff employment, I’m a bit jaded, and not too many items excite me extraordinarily. This unit definitely does. It’s the big brother of the excellent ATN PS-22, with a larger objective lens and commensurate performance. I have to return it, but I’ll get a chance this year to beat the heck out of it in the field, and a tentative hunting trip is already planned for song dogs and night time testing. OpticsPlanet.com will be offering them soon.

Use your standard rifle with daytime optics and install the PS-40 (or PS-22) in front of the scope, and viola, you have a night vision device in front of your favorite familiar riflescope platform without change of point of impact. Clipping this excellent night vision device onto your scope takes under a minute. If you have a long enough pic rail, you can simply attach the night vision device directly on it. The power and performance of this unit can only be seen in fictional movies. It is the real deal, though, and the brightness of the picture is indescribable without seeing it in real life. AND, you get to use it through your regular daytime scope. In this case, it was a Leupold Mark 4 3.5-10×40 with illuminated reticle. Yes, you can still use the illumination in your scope, since the reticle brightness is not enhanced tens of thousands of times by the night vision device like it would be if the night vision device was in back of the scope (or red dot sight) instead of the front. The Leupold Mark IV riflescopes are superb.
I used a mount made to mimic the Larue S.T.O.M.P. mount, but is much less expensive, although certainly comparable. It is made by ATN expressly for the PS-40 night vision device, and ATN calls it the BAM. I thought it may stand for “Bad Ass Mother….”, but the acronym is for the somewhat boring “Boresight Attachment Mount“. Nevertheless, it is an excellent product in most every way. The 1/2 inch attachment nuts should be captive so they don’t get lost, for instance, and if I owned one, I would peen the bolts so they could not be removed. Easily done.

I removed my Leupold Mark IV two piece bases that I love, and installed one of the new EGW (Evolution Gun Works) one piece HD mounts that we will be offering soon. The Mark IV bases are a standard that other bases are measured by, and I prefer two piece mounts mostly because it’s easier to load the gun from the top with frozen, gloved fingers. In this case, the gun was magazine fed and could not be singly loaded anyway, so it was a moot point. Mainly, though, I needed a longer one piece base because the recoil lugs on the BAM mount were spaced more closely apart than what the recoil groove spacing on the two piece Mark IV bases gave me. This new offering from EGW, one of my favorite quality companies, is made of good steel, and has perfect picatinny specs. Any other type than true picatinny is just pretend, and can cause issues when swapping scopes between firearm platforms. As a matter of fact, although Mark IV bases are true pic spec, it matters what orientation the two piece bases are, at least on this Savage. What I mean is that when you have a reversible front base, the position of the non-centered groove in that base may cause a non-picatinny spacing between it and the rear base recoil groove. Again, there may not be the same spacing between the rear groove and the front base groove when you reverse the front base, therefore the spacing error makes it NOT true picatinny. Picatinny is not just the recoil groove width (among other dimentions), but the spacing between the recoil grooves. Anyway, the EGW HD bases are superb, and I recommend them highly, although I wish the Torx screws were number 15 in size rather than number 10. Yeah, I know I’m really anal.

Attach the PS-40 to the underside of the top piece of the ATN BAM mount and leave it. When you need to install it, tighten the two 1/2 inch bolts onto the cantilevered top part of the base and you’re done. I always use my Leupold 65 inch pound torque wrench with a Thorsen 1/2″ deep well socket for these occasions. I can’t live without this tool any more, although the wrench is mostly needed to ensure return to zero as close as possible by tightening the same amount every time, rather than just a secure assembly. Worst case scenario, if you need to, just use a box or adjustable wrench or your Leatherman tool (aaaaarrrrrrrggghhhhh) and don’t cry about it. Just get it tight without twisting the things off.
More about the ATN PS-40 and the BAM mount to come.

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