WesWorld

Quoted

The hinged stock is far sturdier than the frame stock, but is, I
believe, actually heavier than the non-folding stock (weight of the
hinge and all).

True, but I doubt it will double the weight. Maybe an extra pound or so.

Quoted

It does make the weapon more compact for paratroops, but
I suspect that the Yakuza Special Forces would want the solid stock for "conversational use" during interrogations.

I guess for them I need to replace all the wood with steel for additional weight.

Quoted from "BruceDuncan"

The hinged stock is far sturdier than the frame stock, but is, I believe, actually heavier than the non-folding stock (weight of the hinge and all).

I don't think that was my experience, at least. The hinged stock is a bit lighter.