Quoting:
>>OK, I am confused. Some people seem to think that the 5.56 mm cartridge is not working too well on 3rd world types because they are so thin. Now, here, some people seem to believe that century old handgun cartridges don't work too well on modern day American obese people.
Sorry! Can't have it both ways. There are a few cases where modern day expanding ammunition failed to stop very obese types.<<
Actually, given the differences between how handgun ammo and the smallest rifle rounds like the 223 perform, this "inconsistency" is actually possible.
When I say "differences in how they perform" I do not mean "one is better than the other", although that's true too. I mean the wounding mechanism is different.
Somewhere around 2,100fps through 2,400fps depending on who you ask, hydrostatic shock becomes a major wounding mechanism. This allows the narrow-bore 223 to produce wide wound channels, in some cases described as "fist size" if everything works right. One way to describe this is that the tissue the bullet actually strikes moves away from the bullet at speeds high enough to cause more wounding where the bullet did NOT strike.
Handgun ammo isn't usually going this fast, with rare exceptions. You might be able to get 110gr slugs moving fast enough out of a 7.5" barrel 357Maximum for example, until the flame erosion eats the gun.
So with handgun ammo we only get to damage the flesh/bone/fat/whatever that the bullet actually touches. Hence hollowpoints and broad flat noses.
Fat is the tissue most likely to be affected by hydrostatic shock, as it's low in mass. Some soft organs such as brain/liver/kidneys come next. Least affected is very lean stringy muscle, which may be tough and stretchy enough to resist some hydrostatic shock effects.
Upshot: hit a skinny little Somali in the upper thigh with no bone damage with a 223 and the total area of wounding may indeed be lower than the level of wounding for the same hit in the same area with the same bullet on a big ol' fat American. The total area subjected to blood loss may be a hell of a lot different and ditto the length of time each one can stay on their feet and fight (shoot).
On the other hand, with a chest shot the Somali is probably in more trouble with either rifle or handgun wounds. He's got less armor around vitals. His only upside is that they're smaller targets, like the rest of him.
----------
Back to the original question: I would be very tempted to take the LRNs and turn them into a partial flat nose by either polishing the tips on the side of a bench grinder wheel or rub them nose down across a hot frying pan for a few seconds. Done right it shouldn't cost more than 20grains or so weight. With a meplat of at least some kind of size, I think I'd be better off.
If on the other hand I owned a handgun in New Jersey where JHPs are largely banned, I'd think very carefully about these in a 357:
http://www.pennbullets.com/38/38230tndrhd.html
...or a pair of these loaded in 38spl cases:
http://www.pennbullets.com/38/38100dbbwc.html
...or maybe one of those loaded behind one of these:
http://www.pennbullets.com/38/380100TCBB.html