Im going to say one is a Mauser 98 bolt, possibly a WW1 carbine one (small ring action?). The other I would guess is for a 12-ga shotgun built on the '98 action from surplus components after WW1 by the remains of the German gun industry. This is probably quite desirable for someone who has lost the bolt from theirs, or lost the separate bolthead which is prone to getting lost.