Drilled primer pocket holes.

I was going through my bucket of .45ACP brass that I collected over years at the range and noticed that some of the primer pocket holes are drilled to a bigger diameter. (1) Why is it done? Can I use it with my regular brass?
Any thoughts?

Might have been done to shoot wax bullets. I wouldn't use them for regular loads.

I used to drill out primer holes for .32 blanks for starter pistols.
prevented the primer from setting back binding up the cylinder.

if they are Winchester brass the factory actually did that a while back..,something to do with the "green" primers of the day I believe.. they were not the NT brass from Win. but rather the ones marked "Winchester". same as the new stuff that has the more normal hole size...

I've seen smaller holes on Lapua rifle brass, so small I had to modify a Lee decapping pin to even fit through. Figured might have a small accuracy improvement or something. Not sure about a larger hole.

The 220 Russian brass the PPC was made from had small flash holes. So special dies and such. The 6BR Lapua brass I have looks smaller than normal, but I haven't had any issues with it.

It looks like it is not a factory drill. The holes are not perfect, sometimes off the center and diameter is not consistent. So for some reason whoever was loading the ammo drilled it

I bought some range brass and the Federal brass had 3 different size holes (from factory).   I normalized them to the larger size for consistency.