Yes, dear Cait, I put the mixture into hog casings which I get from my butcher. I used to have a special "gun" thing that I got from Lakeland. Unfortunately I lost it when we got flooded out in the Oct 2000 floods, and Lakeland stopped supplying them. I did write to them to find out who had supplied them but they replied snittily that they never revealed the name of their suppliers. After some googling I came to the conclusion that the gun they supplied was in fact a US jerky gun - from the photos it looked identical. I was on the point of asking any kind UKY who was coming over here to bring one for me, when Joss went out and bought a Moulinex electric mincer/grinder that came with a sausage filling attachment (from Argos), so that's how I do my stuffing (oo-er!) now.
I have read that you can use a cookery funnel and the handle of a wooden spoon; and recently I was in a cooking equipment shop which had trigger-driven icing tools which looked as if they could also be used to fill sausage skins.
BTW, forgive my hopeless and profound ignorance, but what is jerky?