Picatinny rail system - Interchangable Scope, Red-Dot and Iron Sight Capability?

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Bill_Rights

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I am shopping for a rifle sight/scope system to mount on a rifle that comes factory-equipped with a top-rear Picatinny rail (MIL-STD 1913 dovetails). Here's one example, the FNAR, but there must be others:
http://www.fnhusa.com/le/products/firearms/family.asp?fid=FNF049&gid=FNG022

What I want is to be able to attach either a) a low-power scope, b) a generic "Red-Dot" style gun sight AND c) iron sights/open sights (or back-up iron sights, BUIS) on the same gun (not at the same time!) and keep each sight's "zero" intact to 0.5 MOA (minute of angle) or better. The purpose is range use with some use out in the field (deer hunting, for the .308 caliber) and home defense. Want tight groups 50-200 yards and close-quarters battle (CQB) ability. For the latter, I consider iron/open sights acceptable, not just "back-up".

I want to be able to make the swap at home or from the trunk of my car with simple tools (no tiny Allen wrenches, etc.) in under 1 minute. Ideally, the different sight-types would be field-swapable with no tools, but I am not holding out for that.

Please forgive if this topic is considered obvious or has been exhausted in other threads - please refer me to those resources!

I started my own research/shopping but quickly got overwhelmed. For example, here is a quick-change sight,
http://www.triggerfin.com/ggandgaccucamqdtrijiconacogmount.aspx
but not sure if a regular scope could be found to take its place, where iron sights fit in, etc.

Thanks for the pointers.
 
Any of the tactical rings as sold by Badger, Leupold, TPS, etc. will get you where you want to be. You need to have each optical device mounted in their own rings, and sighted in to the rifle that it will be used on. Mounting and removing the scope is done by one bolt on each of the two rings. It is recommended that you use a in/lbs torque wrench when installing the scope to the rail, so as to improve your chances of returning to zero.

Don
 
Still need more help with FNAR scope/sight

Yikes! Thanks, members "briansmithwins" and "USSR", but when I look at LaRue Tactical, the prices scare me (> $1000 for a 3X scope and mount?). Maybe I AM the cheap SOB of USSR's tag line, but at LaRue prices, I could buy two FNARs and fit one with scope and the other with tactical sight. The LaRue stuff is impressive, but I am also still confused about all the choices. Nevertheless, I will contact LaRue and see what they can do for me in the way of a complete package - I realize I might get nickle-and-dimed into paying the same amount elsewise and end up with a kluge system, to boot.
 
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You're trying to do something hard, interchange optics on one rifle w/o having to rezero every time. I think Larue is your best bet for being able to do this.

BSW
 
I wouldn't try to put iron sights on the FNAR... I have one and love it, but it isn't a battle rifle, it is a semi-auto precision rifle. Furthermore the front and rear sights would be like 5 inches from eachother meaning they would be practically useless. If you aren't going to be shooting further than 200 yards consider getting one of the aimpoint (9000l) low zoom scopes like this in 2x

http://www.opticsplanet.net/aim-point-9000l-red-dot-sight.html

That price is steep though, I paid 250 for mine through midway when they were having a sale. They currently don't have any in stock.
That scope is super-durable, has insane battery life, is a red-dot, aims quickly with both eyes open and is relatively cheap. With my FNAR and the aimpoint I was hitting golfballs at 75 yards.... I know I could hit a deer at 200 yards fairly easily with that combo.

Now, with all of that being said I am definetly going to be buying a high zoom traditional scope for the FNAR when I get the money. The rifle is accurate and could probably be shot to 600 yards or more with a decent scope. But, if you want a red dot with a little bit of zoom for a decent price I'd check out those aimpoints. If you want to spend (a lot) more I'd look into getting an ACOG for it.. that would be supremely cool imho.
 
Iron sights make sense on an FNAR?

Jack,

I agree. You say:
FNAR... I have one and love it, but it isn't a battle rifle, it is a semi-auto precision rifle.
Click to expand...
I got that!

Still, in a (theoretical) low-light, close quarters and/or home-defense situation, it is tempting to consider iron sights for rifles like the FNAR. Of course, that is not the FNAR's strong point, and it is something like putting a snow plow on a Bentley or a Rolls Royce luxury car. Check!

To one of your other points, about the 5-inch sight radius, yes, that would be foolish. I guess your 5-inch radius comes from the length of the top Picatinny rail as the forward-most possible location for the front sight. I was thinking of putting the front sight at the muzzle-end of the barrel, as usual. An early review fron Shotgun News shows a photo with the top muzzle-end of the barrel drilled and tapped, presumably for a front sight:
http://www.fnhusa1.com/PDF/reviews/0810FNARshotgunnews.pdf
However, a more recent review on gunblast.com does NOT show any such mounting holes:
http://www.gunblast.com/FN-AR.htm

So, uhhhh, I don't know what I am going to get when my FNAR arrives, nor what I will end up doing.
 
I just looked at my rifle to make sure... it isn't tapped for a front sight. I have the heavy barrel model.

Still, in a (theoretical) low-light, close quarters and/or home-defense situation, it is tempting to consider iron sights for rifles like the FNAR
Click to expand...

Yeah, nothing beats irons for reliability. Still from my experience a low zoom red dot like the aimpoint or an acog is very effective in lower lights, even at very close, in home, ranges. If you keep both eyes open it almost gives the illusion of no zoom, but projecting a dot on the target... it's hard to explain but easy to pick up on once you try it.
 
Picatinny rail SYSTEM not repeatable for accuracy upon change-out of optic??

Thanks Jack, Leadhead, USSR, Brian,

So, what I am picking up is, you couldn't even remove and put back the same optic from/onto the Picatinny rail of the same rifle repeatedly (or even once!) and expect the optic to remain zeroed to the rifle. DRAT! I am guessing, this state-of-affairs is because the "joint" between the optic and the rail isn't designed for that. The rail itself is hard-fixed to the gun and does not move. The slot for the rail is hard-fixed to the optic and does not move. It's just that the mating of the rail to the slot is sloppy, in the mechanical sense. Correct?

Probably none of us are mechanical designers, but could it be done? I mean using the rail/slot with the repeatability LaRue Tactical apparently gets with their mount system? (post #2 in this thread and link within)
 
I can't see the accuracy suffering enough to be noticeable for hunting/defense if you use decent rings....

I must say though I have never shot a 1 moa 5 shot group.....
 
It's not the rail, its the rings. The Picatinny Rail will allow you to add and remove optics without losing zero, but it is absolutely critical that the mounts you use will remount accurately. That's why the LaRue stuff is expensive.
 
Thanks, Leadhead and owen - I made a decision, for now

I ordered the Millett DMS-1 Tactical 1-4x24 and a pair of Burris Tactical Xtreme 30mm rings, lightly used. Actually, I bought the lot from a THR member - reference to be posted once I see how the transaction finishes, with his permission if things turn out right, without his permission if he screws me (which I am 99% certain he won't).

Should be a tight, versatile little set-up on my FNAR.

owen, I get what you mean about the rings. If you're using rings at all, even a small scope like the Millet needs two rings (for better initial alignment to the barrel, for optical stiffness, for ruggedness against dropping/hitting, maybe more). So if you take the scope and rings off the Picatinny rail as a unit, you need it to go back onto the rail as an identical unit. Else need to re-zero. Trouble is, two rings clamped on a tube is not designed to stay as a rigid unit, except when all fastened to a receiver, barrel or rail and never monkeyed with.

What might meet my originally posted (OP) desired requirements is a single "sled" that would take the place of two loose rings. I guess that's basically what the LaRue system incorporates. I don't know why that would add $1000 to the overall price - I believe I could cut one out of an aluminum billet in an hour if I had an end-milling machine and some relatively common tooling/bits/cutter-heads.
 
Trouble is, two rings clamped on a tube is not designed to stay as a rigid unit, except when all fastened to a receiver, barrel or rail and never monkeyed with.
Click to expand...

Huh? Two tactical rings fastened to a scope are going nowhere when the scope and rings are removed as a single unit. I carry a backup scope mounted in Leupold Mark 4 rings in just that configuration.

Don
 
I must say though I have never shot a 1 moa 5 shot group.....
Click to expand...

Me either, actually maybe once or twice, but it was mostly pure dumb luck. The internet folks always seem to shoot better than the real folks I meet.
 
stability of loose scope-and-two-rings unit?

USSR,
You said:
Two tactical rings fastened to a scope are going nowhere when the scope and rings are removed as a single unit.
Click to expand...

That's good news. I am glad that at least somebody thinks it's workable. Maybe I mistook what owen was trying to say. I will look at Leopold Mark 4 rings.

I was thinking that the torques and forces of tightening the ring-bases to the Picatinny rail would warp/twist the metal somewhere along the structure. Maybe a broad, beefy "foot" or slot housing to engage the rail would minimize this. I also recall that you said:
It is recommended that you use a in/lbs torque wrench when installing the scope to the rail, so as to improve your chances of returning to zero.
Click to expand...

Check!
 
torque driver and 1 MOA

Thanks USSR (Don),

I take it that the photo is of a torque tool of some sort. I'll mess around with enlarging it later, but you could also tell me the mfgr and model.

About sub-MOA groups. I admit I am an internet gunner, for the moment, when it comes to rifles. I started this thread to help me get a flexible scope/sight system to achieve MOA patterns, among other things. I had just been notified of the delivery date of my first rifle since childhood and needed to get something to put on it, aiming-wise.

As far as actually shooting MOA groups, I thought I'd start with a rifle that at least claims to be able to do it - that way, if I don't get MOA it's my fault. My other "requirement" was .308 semi-auto w/20-rd mag. The only thing I could find that met both reqts was the FNH USA FNAR. The other possibilities, the FAL-derivatives
http://www.webarms.com/Gun%20Suppliers/DSA/dsa%20sa58%20predator.htm and the ARs in .308
http://www.webarms.com/Gun%20Suppliers/dpms/dpms_LR%20Rifles.htm don't outright claim sub-1 MOA, out of the box. I am sure they could be brought up to it, but, uh, do I want to do that?

Anyway, I've put some money where my MOA-th is. We'll see what groups I get when the goods arrive....
 
Bill thanks for reffering me to your post. I am looking at the Millet and Aimpoint for my FNAR also. (thanks to all the good advice here) I want to see if I can find a place that has both. May look through them side by side.

Bill have you found a source for mags yet?

Thanks,
Greg
 
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IME, the issue with getting guns to shoot is finding ammo that the gun likes.

They guarantee MOA, but with what ammo. They are probably using GMM, which isn't even remotely cheap.
 
One more vote for retaining scope zero when changing scope-and-rings unit

The Millett DMS-1 Tactical 1-4x24 and a pair of Burris Tactical Xtreme rings arrived today from a loyal THR seller. All looks good. I don't have to post a photo for just a scope, do I?

I write to say that, just skimming through the Millet user manual, they say that their "Grabber" rings repeatably return to zero after quick de-mount/re-mount. The Grabber has a finger-wheel to tighten the ring base to the rail. I guess the fact that the scope body is a one-piece tube of "heavy duty" wall thickness helps keep the rings stable once they're clamped to the scope body but off the rail.

USSR and Leadhead, you are saying that any good rings should do this, esp. if you tighten things down uniformly to spec with a torque wrench. In that regard, Millet Tactical Rings look better. They have a rail-clamp nut that you could actualy get a torque wrench onto, versus the Grabber's finger-wheel. Also, the Tactical has 3 cap-clamping screws on each side of the cap vesus the Grabber's 1 screw on each side. I guess the Tactical rings ARE better for accuracy and precision - the Grabber is better for quick field change with no tools.

Anyway, for now, I got the Burris Tactical rings, which look just like the Millet Tactical rings, and I got nothing to swap it out for, so that's what I am starting with.
 
You will be stoked when you get to the point of shooting this gun that requires you to check the "torque" of your rings to get that last 1/4 moa!:)

Post a picture when you get it all set up and also when you shoot a nice moa group.....Good Luck!
 
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