I guess the analogy I would use would be to ask what size hamburger will you get in a restaurant? Just as that depends on the restaurant, so too does your question depend on the processor.
    If you go to a high volume, don't turn anybody down, and whack & sack as fast as you can operation you will not get as much as you would from someone that limits the amount he takes and can spend more time taking off the meat.
    It also depends if you're talking straight ground venison or a mix like we recommend.

    If you brought it to us we would expect to get at least 55% of the dressed weight back in boneless meat or 66#.
    To that we would add 16.5# of pork (25% of 66#) and 8.25# of beef (12.5% of  66#) your grand total of hamburger made by us would be 90.75#. (66# + 16.5# + 8.25#)

    Anywhere else you could expect somewhere between 40# - 60# plain venison burger. (My guess)

Dave