I recently saw a Belgian made rifle stamped .243 NORMA. Anybody know what this is?

6mm norma xc? A faster competition round than 6mm br.

Also stamped H. MAHILLON BRUXELLES. Belgium, I think.

Perhaps the "Norma" was simply a hint as to the preferred ammunition. Did the rifle have fixed sights?

Rifle has double rear sights. Lower is fixed and marked 100. Second sight is higher and folds.