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Gary O
06-16-2007, 9:00 AM
Could you folks suggest a combination that would allow me to mount optics on my A4 flat top and still get the scope high enough and forward enough for decent eye relief? I was thinking that forward enough would mean just forward of the latch. Some kind of “scout” set-up? To complicate matters I also wish to use folding BUIS’s. I guess that means I need something that will leave room at the rear of the flat top to mount the folding rear sight. Any help would be great…
Gary O
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Socal858
06-16-2007, 9:26 AM
easiest way would be the larue mount. itll set you up a few inches upstream of hte latch so itll be pretty comfortable shooting nose to charging handle. flick tabs and it removes

i have the RRA scope mount, it puts my burris right at the latch. it uses two thumb nuts to secure. i have no BUIS on my 20" rifle i mount it on, just a carry handle; folding BUIS would fit under the scope if i decided to have it though

shark92651
06-16-2007, 10:02 AM
A lower price alternative is the YHM rail risers and rail extensions. I mounted my scope using one of these and Leupold PRW low rings. My scope has a 44mm objective lense and it fits perfect, with just a couple mm clearance above the forearm. All of the YHM risers increase height by 1/2", with various amounts of maximum extension beyond the front of the upper - from 1 1/4" up to 4" depending on which model and placement. I just sold a similar setup to someone with a 50mm scope so I suggested the medium rings - I'm waiting to hear back from him on the fit.

http://riflegear.com/c-31-rings-and-mounts.aspx

Jicko
06-16-2007, 10:09 AM
Could you folks suggest a combination that would allow me to mount optics on my A4 flat top and still get the scope high enough and forward enough for decent eye relief? I was thinking that forward enough would mean just forward of the latch. Some kind of “scout” set-up? To complicate matters I also wish to use folding BUIS’s. I guess that means I need something that will leave room at the rear of the flat top to mount the folding rear sight. Any help would be great…
Gary O
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You'd need to raise your scope about 1.25 - 1.5". ARMS got #22 HIGH, which is like 1.5" off your flattop.

If you want the scope to be mounted FORWARD, Larue and Armalite and a couple other companies make those forward/scout like 1-piece mount.

RE: BUIS, you would need a low-profile rear sight. ARMS #40L (.6" off rail, it can stay low enough to clear the eye piece) works, and KAC've got 2 that works, one for 200/300m, an another for 600m. Troy also have one, folded @ only 0.46".

ARMS: http://www.armsmounts.com/
Larue: http://www.laruetactical.com/
Troy: http://www.troyind.com

http://i95.photobucket.com/albums/l133/mjpjr45/SPR14.jpg

The rifle on top, Larue mount, Troy BUIS, Trijicon scope.

maxicon
06-17-2007, 1:27 PM
Yep, the LaRue or an extended rail with rings would be the best bet. The Armalite may not leave enough room for the BUIS under the scope eyepiece, but that depends on the eyepiece diameter and the BUIS height - see the pic below.

For the rail, you'd need one that left room on the flat top for the BUIS behind it - many, like the RRA rail, don't. It looks like the YHM rails do, but I don't have one to play with. Maybe shark92651 can clarify.

The plus of the rail and rings combo is that you can try different eye relief and ring heights to find something that works for you, but there are more connection points to loosen or shift. The one-piece is more solid and quick to remove so you can switch to BUIS, and usually has better repeatability.

You can see on Jicko's mount that the LaRue gives plenty of eye relief, clearance below the eyepiece, and room for a BUIS on the rail. They're a bit pricy, but are considered the best one-piece. A lot of folks over at arfcom say they spent enough on trying other solutions to buy 2 LaRues before they went ahead and sprung for one.

Here's a pic of the Armalite mount with a Mueller 4-16x50 scope and an ARMS #40 BUIS - as you can see, there's not enough room. The #40L or Troy BUIS might fit better.
http://www.maxicon.com/guns/ar/varmint_mueller_armalite_arms40-a.jpg

And the RRA rail, which is good but doesn't leave room for a BUIS:
http://www.maxicon.com/guns/ar/varmint_leup_clone_rra_scout-a.jpg

Here's a GGG scout rail, which leaves a slot open at the rear, but there's about 1/16" or so interference that keeps the ARMS #40 from mounting there:
http://www.maxicon.com/guns/ar/cmmg_ggg_scout-a.jpg

Jicko
06-17-2007, 1:51 PM
Here's a pic of the Armalite mount with a Mueller 4-16x50 scope and an ARMS #40 BUIS - as you can see, there's not enough room. The #40L or Troy BUIS might fit better.

Basically ARMS #40 (regular) is NOT to be used if you want a BUIS underneath your eye-piece. #40 (regular) is almost 1" (.95") above the top of the rail, so it won't work (period).

Use #40L or Troy's.