Bulk Sausage Grind????

Pre-ground meat will save you a significant amount of time, but possibly at the expense of knowing the lean to fat breakdown and grind plate measurements.  You mentioned that you wanted to experiment, and knowing these things are important if you want reproducible sausages.  But you can also just eyeball it; or depending on how well you're paying your butcher, he might get fancy for you and do X number of packages of course-ground/fine-ground but my guess but you still might be guessing at the fat content.  If you really want to get specific about it, you would get lean meat and fat separate so that you would always be in full control of the fat content on your sausages, but that's a lot of work for the guy doing the cutting.

Perhaps if you had him separate the packages by cut, meaning the butt grind is in one package (and only the butt grind), the tenderloin is in another package, etc, you would have a better idea of the fat content in each package (I'm sure there's something on the internet that says the average fat content of specific cuts of pork).

Or maybe I'm overthinking this and the average fat content of a pig is 35% (I'm guessing) so you can just have him grind up the whole damn thing.  

KA Stand grinder doesn't do well on pre ground meat...   The auger does not fit tight in the barrel of the grinder....   The meat will smear on the second grind.....   If you don't get a new grinder, about $100, have the meat chunked into 1" cubes...   Season and add what-ever to the chunks before grinding...   grind once...  then stuff....   OR if you use the KA as a stuffer also, stuff into casings as it is grinding the cubes...   meat just doesn't do well 2 times through the KA....   each is less than $100...   Northern tool for the grinder..  Grizzly for the stuffer....

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