You definitely want to check out the G1-OSM made by GDI Engineering, which is – or was – also sold as the Trijicon TA70. It's got a solid 3-point attachment system (side locking screw, stripper clip guide mount and contact screw to the receiver) and sets the 4x32-ACOG back far enough to not being compromised by its fairly short eye relief, if combined with the right lenght of pull. Also, the OSM doesn't obstruct your iron sights and lets you keep them as a back-up option (assuming, of course, your – highly recommended – cheek riser isn't permanently fixed to a certain height). As you can see, the ACOG mounts directly to the holes in the OSM, thus there will be no need to use an ACOG picatinny adapter. This keeps the optic system's profile as low as possible, considering it's sitting right above your rear sight.
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What kind of stock are you planning to use on your SOCOM, anyway? To me, the stock of the EBR chassis being rectracted two steps from its fully collapsed position seems to be ideal. That setup is a fair amount shorter than the synthetic M1A stock, so using a standard rifle stock would not only need to be compensated height-wise by a cheek riser, but also very likely compromise your eye relief to some degree or another.
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