It must have been for export with the No Bullet, which denotes the exclusion of ball ammo not slug.
Not for Ball
Non Pour Balle
Nem Golyonak
Jen Pro Broky
Nicht Fr Kugel
Also the FN stamp for Fust Nelkuli has been replaced by the Smokeless term, possibly also noting export
Into on the Hungarian proof facility is sketchy at best. But what they did try to convey thru marks was:
Nem Golyonak - Not for Ball noting constriction
Proof number / year
Tubeset weight in grams
Bore diameter measurement taken between 15 - 22 cm from breech
These should always be present & it would seem that there are slight variation depending on the time period & reproof or not. Also having different constriction in each tube may produce a variation.
Red encircled - Nominal bore data - measure right tube at muzzle to compare vs. 18mm
Green encircled - Constriction measurement
Blue encircled - weight of tubeset
Yellow encircled - sequential proof number for the year over year
I'd say the circular or radius of metal was left for side frame reinforcement and may overcome some internal removal of metal. Now the screw, I'm assuming you are referring to the one adjacent to the cocking or loaded indicator?
Kind Regards,
Raimey
rse
