Try the Brookfield Precision Tool or the Smith Enterprise mounts. The BPT is used on the M-25 and is a good solid mount, but it not a fly-weight piece of equipment. The Smith is a near clone of the BPT. Another decent mount is the Leatherwood. This is used on the M-21 and is also pretty stout. You are not going to get a lightweight mount that will hold a solid zero on an M1A. Between recoil, bolt operation, etc. there's just too much violent motion taking place for a lightweight unit to withstand. I would look somewhere else to try and save weight and leave the beef in the critical components. Good luck
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