I'm new to reloading, and in a bag of brass I bought, i found some which, due to a lack of an extractor groove will not fit into the shell holder which came with my Lee die set.

Would I rectify this with a larger shell holder or are these just a waste?

What brand of brass?

No company is without its share of dud shell holders. You could alter that one if your are careful or just buy another brand. I would try RCBS because of their customer service.

The other thing you might do is call Lee and ask them about the fit. They sell shell holders with several sets of dies that are known to be poor fits.

I find two head stamps, most are REM-UMC (Remington/Union Metallic Cartridge) and one marked WRACO (pre-1932 Winchester).

It would appear that the problem brass is of the older design, and fortunately only a few aren't fitting the stock holder. But, there are 40 of them so a cheap fix would be good. Otherwise I'll just see if the reload guy at the gun show will give me a few bucks off something for them.

Dan check in the older cases in case they are of "balloon head" design.

If you peer into a modern case from the front, you should see that they are relatively flat sloping toward the flash hole.

A balloon head case isn't flat there, but sort of has a doughnut round the flash hole.

These cases are a lot weaker than the modern ones, and may even have been fired with mercuric primers which would weaken the brass.

Maybe someone can tell us more, that's the sum total of my knowledge on balloon heads.

It is not your shell holder.
Yes, the manufacturers changed the 45 brass sometime back; I am thinking in the 70s. Because the rim was too small and it kept slipping out of shell holders. Remingtons were bad for that back when I started to reload them. The original 1873 45 brass had a very small rim with no extractor groove, and was NEVER put into a rifle. So, get rid of all that old brass and buy some star line; it is very thick and will last much longer than any other brand. Your 1932 brass is probably not balloon head but because of the rim thing, forget them.

Dan,
I would agree about the old brass. It is not worth much. Why worry with it?
Buy a good supply of new brass and focus learning to load with good components.