looking to buy a bulk supply of self defense ammo, need some help.

I got a bonus from work and decided to spend it on some ammo at the gunshow coming up here. I usually just use federal xm193, but I feel like spending some more money for something better. I’m thinking hornady tap (thinking 75 grain). I’m looking for a self defense / home defense / SHTF (might as well cover that while I’m at it) round. So, if you have any more options feel free to post them. I’m sorry if this question sounds dumb. I just really need some help in the matter. I have searched and read some about people liking the 75 grain hornday, and am looking for more options.

Thanks everyone in advance.

Have you read THIS: https://www.m4carbine.net/showthread.php?t=19881???