Just a friendly reminder and word of warning if you are freezing your stock in mason jars. LEAVE HEADROOM.
I left less than an inch of headroom in this jar, and found it cracked in the freezer. All is not lost though, the glass came off amazingly well in several large pieces. It was then melted, run through a fine mesh strainer and cheesecloth, and since it was already out, turned into beef gravy.
But please, leave headroom even if you aren’t pressure canning. The freezer can do damage as well