A friend did some extensive testing of .44 Special ammunition several years ago when he wanted to carry his S&W M21 Thunder Ranch Special. He did both tests bare into gallon jugs of water and and with clothing covering. He sent me pictures of the results which were dismal. At velocities .44 Special runs bullets there is no guaranty of expansion and even when they did it was not that much. Even the Speer 200 grain Gold Dot HP only opened a little.
He was very disheartened and ended up buying one of the 629 3" Performance Center guns with the port on the end of the barrel. He then sent pics of several loads including the Speer 200 grain Gold Dot .44 Magnum Short Barrel load that although uses the same deep HP as their .44 Special load, this listed velocity from a 4" gun is 1080 fps vs. the .44 Special load at 860 from a 6.5 barrel. This time the bullet opened EVERY time to the point that occasionally a petal would break off.
Me personally, if I was carrying a short .44 I would look to a wide meplat at a modest velocity I could control...
Bob
