I've found that Hornady and Federal brass fit fine in my (correct for caliber) shell holder. Geco, RWS and S&B don't.
Presumably different manufacturing specs on the brass, but surprised at the difference.
Is that normal?

If they don't fit at all then no, cases should all be made to SAAMI specifications (where there is one) so they should all be within a fairly tight tolerance.
What calibre are you using?
I used to shoot 303 and try finding an American made bit of brass for that that is anywhere near the correct size. The rim diameter is too small the case web is undersize and often the rim thickness is wrong as well. No wonder the 303 has a rep in the US for eating brass as it has to over expand just to reach normal sizes. May I usuggest to measure some American made cases and compare them against the case specs. Bet you will be surprised at how far out they are.I had problems with some S+B brass in a Lee shell holder, it was just the outer corners of the holder that were preventing the brass entering - I put a radius on the corners with my Dremel and it fits perfectly now
this happened with some match .222 norma brass I bought
slightly different headstamp and the groove of the extractor is a little tighter
Sorry to but in but in my 7x57 I have found that Hornady cases are slightly shorter to the shoulder than RWS- enough that you can see the difference. I have found that primers on Hornady ammo are slightly proud after firing. The Rifle is a Rigby built in the mid 1970s.
I've just noticed that with some Norma .223 brass I've got. Some has stamped headstamp and the other seems to be faintly etched? Any idea if there's a difference between the two?

I purchased some "match" brass, came in boxes of 20
they are marked like the one on the bottom
the one on the top is factory ammo reloaded
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