I ground up 4 lbs of beef yesterday....bought 2 1/2 lbs chuck
steak & 1 1/2 lbs boneless short ribs....sliced 'em all in strips about an inch wide, seasoned w/ 2 tsp/lb Old Bay...chilled in freezer for 45 mins....had the KA Food grinder attachment in the freezer also...salt & peppered all the beef...put the KA on speed 4 and ground away.
Some complain the KA is not up to the task....overheats and so forth....take a look at the worm gear's driven end - the square part - it's easy to turn w/your hand....put back in the body, attach blade and plate and
just snug up the retaining ring - you should still be able to turn the driven shaft ok with the ring just snug...now turn the retaining ring a little tighter and you probably won't be able to turn the shaft - no matter who you know.... that will probably heat up the stand mixer just to overcome the ring's friction, let alone grind meat.... anyway, if mush starts coming out , just stop, clean any gristle off the blade and let 'er rip.
I cook 'em in a cast iron frying pan or cast iron griddle with a blob of bacon drippins' ...never have put 'em on a grill.