The 230 is intended for the 45 ACP, but may work well enough in the 45 Colt if you place it well. There is no cannelure to crimp into, but as you are not running them real fast they should stay put under recoil. I'd be skeptical of the 300 at such a slow MV, and it will be travelling even slower by the time it gets to the target. Given only the two, I'd go with the one I could drive fastest.

You don't necessarily need pass through penetration, but you do need to get to the vitals and do some damage. Pass through penetration without expansion is not really a good recipe with that nose profile.

Do you have a chronograph to verify the velocities?