7.62 NATO will fuck you up. And the guy behind youThe C1A1 was well before my time, but when I did my infantry DP3A (small arms instructor course) in 2012, we have a famil on various firearms that included getting to shoot the C1. That was truly a treat. We also did a penetration shoot on cinderblocks, sandbags, etc that gave me a healthy respect for what that sort of caliber is capable of.
My serial number on my FN from Cornwallis in 1983 was 0L0608. I remember the first time that my MCpl asked me for the SN, the second day of the course. I looked at him, completely befuddled, and the spent the rest of my day being "cocked" because I did not know the SN. I memorized it, and, 38 + years later, I still remember it.The only time I used the .22 insert with the C1A1 was in Chilliwack on BOTC. If I recall correctly, there were a few minor feed problems but nothing that seriously disrupted the serial. The only experience I could compare it too was several years later at Fort Sam Houston (outdoor 25 yard range) when we shot the M16 using the .22 rimfire adapter kit but with store bought ammo (a bunch of us needed a recent range qual before going to an EFMB test). About every half dozen rounds mis-fed, it was a pain in the ass to get through the shoot.
But I fondly remember the FN. It was a real rifle.
6L2439 was replaced by 87AA 5440 for me.3L5 358 rack 47 does not get any better than that. do not recall its replacement number other 89AA something, they all looked the same. Black and shiny, my C1 had scratches, dents, and dings. If you ran out of ammo, you could swing it like a club the Oak made sure the guy was going down.