Will the ARMS Aimpoint throw lever mount, mount on a ARMS #18 M1A mount? DO I just need the mount or is there something eles I need? DO the rings come with the mount?



Thanks

ARMS invented the picatinny standard for mounting rails, so any picatinny standard ring will mount properly on an ARMS picatinny mount (like the #18). If the aimpoint ring you are refering to is the #22m68, it should have no problems at all. I'd mount the ring on the furthest forward position.

The ARMS #18 mount for the M14/M1A does not come with rings.  It is an outstanding mount by the way.  The lowest possible mount for the M1A that allows iron sight use.  Where others raise the mounting platform high enough to sight under the mount, ARMS, lowered the platform so you can sight through the groove in the top of the mounting rail.  By using ARMS #22 rings, you have a clear channel down the center that aligns with your irons.   It is a GREAT system, probably as solid as the Brookfield system.

One caveat.  I do not know if the #22M68 rings allow sight through when mated with the #18 mount since the #22M68 was originally developed for the M16 family. I'd email ARMS and ask them.

In theory, this combo would seem to be good, but in practice is not. On Extraction/Ejection, the casing will bounce off the rearward portion of the M22#68 mount and Aimpoint. This interfers with the ejection prossess and the spent casing will not  be ejected clear during the cycling, resulting in failure to load the next round. This was with the mount having the locking mechanism/lever mounted on the left side of the gun, firing approx. 100 rds with better than 2/3's of the rounds failing to properly cycle the action. Tried it with the lever mounted on the right side but after less than a half dozen rounds the gun went down and have not been back to try again since the repair.

On another point, you can buy the top portion of the M1A that is on the Scout model.  This gives you a picatinny standard well forward of the breech.  This should allow mounting close to the sight (probably co-witness capability) and minimizes the number of additional mounts you need.  
check out the Springfield site