· Diamond Member with Oak Leaves and Swords
I'm pretty sure the Germans considered a rifle a carbine when it had a turned down bolt and side mounted sling, like the Kar98a of WW1 vintage. They did in fact name the Karabiner98b because of the turned down bolt and side mount sling, although it was the same length at the Gew98. Those rascally Germans.[/QUOTE
It is what contemporary competent authority said what it is; don't look for logic beyond that.
BTW, the Kar 57 (needle gun) had a straight bolt and sling ring; the (Saxon) Kar 73 and the Prussian altered Chassepots (a.k.a. in some sources the "altered Chassepot" and /or "Prussian Kar 73") had bent bolts and belly swivels; the Werder Kar 69 didn't have a bolt at all and had a sling ring; the Kar 71 has a bent bolt and belly swivels.
For the purpose of your article establish your own criteria, specify it , and go from there.