Thanks for the help guys. Y'all are pretty much confirming what I was thinking. But I appreciate good discussion and thought out opinions I like the multiple mags idea. I would likely have at least one spare mag anyway; so it might be best to carry multiple ammo types: penetrating and expanding. I can load up whichever I think is best for the most likely threat and carry the less likely as spare.
The hardcast stuff would probably be pretty good for penetrating, but I'm hesistant to run lead through my stock Glock barrel.

For those of you who have guns that will take them and consider snakes a problem, the shotshells are a good idea. Call me weird, but I don't consider snakes a "must shoot" threat. I'm going to be hard pressed to kill one or let someone I'm with kill one unless it is venomous and hanging out in my front yard or the equivalent. If I'm out in his home turf, he gets the right of way and the right to live. I recommend reassessing your need to shoot them, but I won't judge.

I've looked at the doubletap stuff in various flavors and will probably order some to try before long. I really want to get some ammo that brings out the full potential of my 10mm. I didn't single it out as the main focus here because I felt this topic would be best served on a broader caliber level. I think you've done well on that so far, and I look forward to any further discussion.
Thanks again.