Best Extended Scope Rail for AR
If you mount a large, high-magnification scope on an AR15, AR10, or AR-based space-gun, you’ll need to set the scope well forward to allow proper eye relief while retaining normal length of pull. (Buttstock extensions will move you far enough away from the rear eyepiece, but then you may have to reach too far to the trigger.)
Robert Whitley, who regularly uses scoped ARs and spaceguns, recommends the GS-1 extended rail from GG&G. This allows you to put the front scope ring out front of the receiver. The rail fits any flat-topped AR receiver with a picatinny mount, and retails for $89.95 at 6mmAR.com and other vendors.
I’m curious how this compares to the one from RRA: http://www.rockriverarms.com/item-detail.cfm?ID=AR0134&storeid=1&image=rrscout.gif&CFID=37891641&CFTOKEN=29164536
What would make one better than the other? The RRA model doesn’t have rail all the way to the rear, but I’m not sure that’s a negative.
I don’t know what the technical specs are on the RRA rail, but the rail needs to come forward at least 3″ forward of the receiver to get enought eye relief for scopes like a Leupold or Nightforce that have a long eye relief, and the GG&G rail does this.
Robert Whitley
White Oak Precison has a nice one with 15minutes elevation machined in. http://www.whiteoakarmament.com/