Various 8mm brass inside neck measurements...Norma .013 , RP .011 ,WW .014 ,S+B .015 ,Dominion .012 and my formed Browning .018 May be a little thick?
You won't know until you try it in your chamber.
IMHO, the thicker you can keep the neck the better.
The brass I'm shooting in my 8x57 sporter is old Gevelot, black box. It was new unprimed and came in boxes of 20, with all French language printing.
The necks on this stuff measure .015 and with .323 Norma Oryx, 196 grain bullets have .0015 clearance all the way around.
This is as close to perfect as it gets for me.
They chamber well and the combination, with the load using CCI250 primers, 56.0grns of H414SL10 (slightly slower and less temp sensetive than W760, commercial surplus powder) out of a 23 inch barrel, shoots into sub moa at 100 yards, giving 2600+fps.
That's a snorting hammer of a load IMHO.
I'm glad this rifle turned out so well. It was a put together from bin parts rifle.
I had a lovely old Walnut stock, with Maple tip, Pewter grip cap, Brno 21H double set triggers/guard/floorplate, set up so the front trigger can't act as the release trigger, until the set trigger has been pulled. Makes for an excellent and very fast safety.
The receiver was an old take off D&T, with ground surfaces for scope bases and a cut back take off 98 barrel in exc condition.
Looks like it's right out of the early sixties, other than the Burris scope and commercial shroud. I like it a lot.