I have been owning two M66 since the mid/late 70's, they were the first 'real' rifles that I acquired. They are one in 7x64 (proofed in 1972 and scoped with a Zeiss 1,5-6x42) and one in 8x68S (proofed in 1976 and scoped with a Schmidt & Bender 2,5-10x56). They are extremely well manufactured rifles, extremely accurate and a pleasure to use.
Production ranged from 1965 to 1995 and 58,765 units were manufactured.
Louis