This is a discussion on Need help picking m14 scope mount within the Optics forums, part of the Gun Forum category; I've narrowed it down to
A.R.M.S. #18 M21/14
Sadlak Industries M14/M1A Aluminum Scope Mount...
You don't say what the mount will be used on but if it's an SAI M1A, there is the possibility of fitting issues with the ARMS #18; the horizontal position is fixed by the vertical key and if the stripper clip guide dovetail on the receiver is too close, the rear of the mount will ride up on it. Most other mounts, including the Sadlak, can compensate for that. That can also happen with other M14's but seems to be more common on SAI.
I just ordered an ARMS 18 yesterday and Burris extreme tactical rings, the low mount version for my rifle. I want mine as low as I possibly can get it. Even if it means I cannot use the irons with it on.
I previously had the Sadlak aluminum mount, lost it when my car was stolen with the mount in the car. I did like that mount a lot as well, though I did not get to do a lot of testing with it before I lost it. However I still wanted a lower mount, so that is why I chose the #18 this time.
Not completly sure the rings will work, if not I have a set of mediums and I'll put the lows on my 700P.
I will most likely will have to play with ejector spring lenght too as I expect cases to get caught between the mount and op rod. I had this problem on occasion with the Sadlak.
Really looking forward to getting it and mounting it. I need take my eyes and my struggles to shoot irons here lately out of the equation to see how good this rifle really can group with my latest loads.