I saw a list of the required KE for different game and I know that the higher the momentum the better.  The question is, exactly how much momentum must an arrow have to consistently pass through an adult average-sized whitetail?

I checked online and came up empty.  Any ideas?

Well... that would depend on where you hit it, and from what angle.

Do a post search here and I think you will probably find more on the subject than you want to read. I am afraid that even if you read all of it you still will not have a firm answer with reason behind it.

I don't really worry about the numbers anymore to be honest. I know my 50# bow with a 600 grain arrow does the job. I have had pass throughs even at fairly drastic quartering shots. Not quite end to end so to speak, but certianly back rib to front shoulder at an average of 15 yards.

I wasn't much help, but wade into all the posts dealing with the topic on here and you might find some information.

OkKeith

I think Ashby's research has shown that K.E. is about worthless as a predictor of penetration.  Momentum is much better.  Broadhead design, arrow tuning and EFOC and a host of other stuff all affect penetration.

There was an issue of TB that he listed minimum momentum required to kill a water buffalo I believe, some kind of big critter, that would be considered overkill for whitetail.  You might be able to read thru his research that is stored here on TG and find it.

What ever draw weight you are shooting, select a good broadhead razor sharp, with the heaviest arrow you can shoot and still live the trajectory, and tune it as good as you possibly can...That is the best you'll ever do without going up in bow weight or higher performance bow....O.L.

Thanks, Gang.  I'm kind of a perfectionist when it comes to finding the happy medium between arrow flight, speed, and penetration.  I've gone light, heavy and in between.  2-blade, 3-blade, large heads, compact heads.  I'm thinking of splurging and going with a combination of Beman MFX Classic 400 with 300 Xtreem broadheads with right wing Gateway Rayzr feathers.  That should put me over 600 grains and over 19% FOC.  Hopefully my 52lb'er can throw it over 180 fps.  Then all I'll have to worry about is arrow flight.

O.L. hit it dead on.  Shoot the heaviest arrow you can,  and stil live with the trajectory.   Tune it so it flies true,  this is too often given short shrift.  Select a quality cut on contact broadhead,  and don't worry about the danged chronograph.