[AndyB]

X marking should be portuguese inspection, normally the MRD is about 16,2 but could be little larger after heavy using, there is 2016 discussion by Bo.A. about 17,4mm MRD pieces. Barell ring should be measured from blade side, both orientation horizontally and vertically, as it could be bent a little. This piece was already cleaned in time as the edges are not sharp on handle and crossguard.

 

[AndyB]

Personally i dont believe this is new cleaning more real already done by portuguese, the edge of blade is not extra cleaned probably, the engraving is normal weak to see, some are after cleaning not visible. I would tend to variation of some portuguese variant rifle, as the pieces are well done and the crossguard is clearly new not reworked in any way.Wout have it attached on rifles is this not possible to determine, there should be destined a locking distance of Kropatschek bayonets that would be able attach on other rifle.

 

[AndyB]

Problem is the bayonet was not altered to new diameter but made as is with new barell ring, secondly this carbine was done for bayonet attachment by portuguese as it was delivered from Steyr wout bayonet adapter. As You could seen on press button the handle was heavy cleaned, so i assume the 16,5mm its little opened and measured from back side, for Gew88 should be measured the locking lug dimmension and locking distance from back of crossguard to to start of locking lug in pommel of handle.