Small Pistol Primers in .45 ACP?

I’ve been reloading .45 ACP using mixed range pick-up brass, and in the batch I have been processing some 40-odd have SMALL pistol primers, not the large ones I normally associate with this caliber. All of them are Federal headstamps, except one with a Blazer headstamp. All the cases are brass, except one batch of 15 or so is nickeled, the rest aren’t. Furthermore the head seems slightly “dished” on these cases. It’s barely noticeable but it is indeed there.The Blazer case is brass and isn’t dished. I have many other Federal cases, using large primers and without the slight dishing.

So what have I got? Is this some sort of special-purpose ammunition (e.g., target) that Federal produced/produces? What about the Blazer case? I’ve been shooting .45 ACP for years and have never before encountered any with small primers.

These have been around for quite some time. 5-10 years or so. Quite a pain for us reloaders…

Nothing special or unique.