So, correct me here, but if I understand we want to simply remove the flair, and no more?
That depends on the gun. I have two Kimber 1911's, both 3" guns. Basically identical, but what plunks in one won't plunk in the other. So I make ammo for the tighter chamber, and it works in both. You don't have that problem if your only loading for one gun, but you may have that problem in time. Reloading can be addicting.
If your gun will function after just removing the flair, then you're good to go. If not, you may have to crimp tighter like I do.
Keep doing what you did to make those - but with primer and powder - and you will be fine. All the friendly and well-meaning advice can sometimes derail a great plan.
This ^^^ is good advice. Your dummy rounds plunk and feed from the magazine. So you should be good to go as far as your die setup. It sounds like you have it right.
Now, make a few at the start charge, and go up in 0.1 or 0.2 gr increments until max. I don't load .380, but you probably have a small "useable" range, and will most likely want to use 0.1gr increments. This will be your "ladder test".
When I do a ladder test, I usually make five rounds for each charge weight. Next, I go to the range, and try them out, and decide what I and my gun like. I'll take some factory ammo to compare to my reloads, so I have a reasonable comparison.
Once you think you have your load, make another 50 and go to the range again. If it feeds and functions fine, and you're happy with the accuracy, then you have your load. At this point, load them up to your hearts content.
Don't load a bunch before doing your ladder test. You don't want to have to pull 500 (or even 100) rounds apart because they are too hot or they've turned your semi-auto into a single shot.
chris