Goose,
I have to say, I think that depending on the flat nose of a full metal jacket bullet for stopping power is a fantasy and a very bad idea.
The supposed stopping power of the meplat in hunting rounds is often touted, but you should look closely at those hunting rounds. The flat nose is usually near full bullet diameter and sharp edged or is at the front of a cone which sits at the front of a full caliber. sharp edged shoulder that will act like a full wadcutter, in the old KEITH style bullets. I believe it is the tearing action of the wide meplats and sharp edge shoulder at the base of the KEITH style coned bullets that do the actual damage in hunting situations.
Also, those rounds will usually overpenetrate which in a hunting situation is a plus, when out in the countryside. A full penetration means a hole going in and a hole going out to double the blood loss and blood trail.
It is a liability in an urban location.
Another problem is that the small meplats on 9m.m. and .32 caliber ammo are usually rounded at the edge, so they have little tearing or ripping action in flesh. That is the same problem as regular round nose ball ammo has.
Also, in my experience, flat meplats in semi-auto ammunition more often lead to misfeeds and jams. I stopped using WINCHESTER .32ACP ammo for this reason.
Say you actually get into a gunfight and it is fully justified, but you have an over penetration and either injure or kill someone. If you are sued, your justifying "CHEAP" ammo is something that a lawyer would argue shows your disregard for the safety of others and could even get you criminally prosecuted.
NO, I AM NOT KIDDING!
It would be the same if you let the brakes wear out on your car and have an accident. You could have prevented the problem and that can bring liability issues. Your testimony, that you were just trying to save money would probably not go over well with a jury.
Anything you post on the internet is there forever and can be found by a computer savvy investigator. What would be your justification in front of a jury? Hey, I just wanted to save money and did not think it would be a problem! Could you see an opposing attorney letting that lay?
Spend the small amount of extra money on a good brand of hollow point. If you ever have to justify your choice, you can use that to your favor. "Yes, your honor, I bought the same ammo that my local police use because I wanted a round that they had found was not a risk to innocent bystanders"!
You can usually shoot ammo of the same weight, like a 115 grain fmj for practice and an 115 grain hollow point for carry with a box of say 20 rounds to shoot a qualification drill and not have any issues.
For me, a 20 round drill would start at 10 yards with three double taps, then two 3 round failure to stop drills (two to center mass and 1 to the head) at 7 yards and then 4 rounds strong hand only (single handed) followed by 4 rounds weak handed only at 5 yards. You can vary this, but if you can do it, you will be able to show you can shoot your carry load adequately for self defense and compare it to shooting the same drill with ball ammo.
Good luck,
Jim