Which one does more damage a .45 185 grain HP traveling at 1,150 fps or a 230 grain HP traveling at 950 fps at close range.
Well, if both loads are designed to have similar effects, due to bullet design, then the difference will usually be rather small. Ultimately, if one has access to reliable terminal ballistics test data for specific loads, then one should base their choices on that rather than generalities which may not always hold true in the real world.
It would seem to me that the lighter and faster round would do more damage and penetrate better. It will also have more energy.
Theoretically speaking, energy indicates the amount of work that can be done, which in this case is namely damage to flesh and other materials. That said, there are other important factors at play, including momentum and efficiency. While the 230 grain bullet in this example may have less kinetic energy (potential to wound), it actually has greater momentum, which factors heavily into penetration. At least in wet media, according to the many test results I've seen, heavy bullets (that have higher sectional density in the same caliber) seem to give up their momentum and energy more gradually, typically resulting in deeper penetration. Light bullets with higher energy appear to dump more of their energy into the temporary stretch cavity, which while devastating to wet phonebooks and ballistic gel, may well not have much of an effect on flesh with its greater elasticity and shear and tensile strength. In short, some folks believe that the extra energy is merely being turned into a small amount of heat, thereby making light bullets less efficient than heavy bullets, which evens out their true potentials for wounding.
If we then factor in some of the advantages of having a larger bullet, such as a greater potential to expand (even at lower velocities with modern bullets), greater length that causes more damage if the bullet yaws (some light bullets look like disks after they've fully expanded), and less blast & flash with typical barrel lengths, then we can see why some people prefer heavy-for-caliber bullets. I think they're advantageous for relatively short barrels, as well, because light bullets need more gas to get their momentum high enough, and short barrels will waste even more of the generated gas than full-length barrels (the assumption is that at equal pressure, more gas requires a longer barrel to be fully utilized).
But both of these being .45 ACP will still make big holes so maybe it doesn't make a difference at close range?
They're still small holes in comparison to the size of the typical target of a self-defense shooting. .45 ACP might look big next to 9mm, for example, but the difference isn't much in comparison to the target. Within reason, bullet weight makes even less of a difference, although it doesn't hurt to figure out what is the most optimal load for one's own sensibilities (for peace of mind, if nothing more).