i've had off centre primer holes in S&B brass , snapped de-capping pins in FLS dies before i took a look at a couple of cases and it was obvious to the naked eye . i bought some old "highland" (PPU) 303 ammo from a well known brisbane guns shop that ruptured cases. after firing five, i took the ammo back for a full refund . i also took a fired 303 remington case, as i switched to that , and my rebarreled 303 martini to show it wasn't the gun/chambers fault. never had a problem with rem brass in that rifle after multiple firings. as another member posted above , European 7x57 rounds must be made to different specs as you need a different shell holder to reload it , norma 7x57 you don't . norma must be sammi spec with its rim and extractor groove dimensions . my ruger m77 in 7x57 needed work to the extractor as i had ejection issues after using the PPU brass . this could have easily have occurred using S&B brass. my rifle with norma brass feeds and ejects flawlessly with norma, i won't be using any other 7x57 brass in this rifle from now on . would this issue have occurred with the PPU 7x57 brass in a mauser 98 ? probably not as it was designed for the 7x57 and it's euro specs.
these have been my first hand experiences , nothing manufactured has a iron bound guarantee to be free from faults . part of the 35 whelen head space issue "myth" cause of it's small case shoulder, can be traced back to a batch of rifles by a american maker that had the chambers incorrectly headspaced and rumored factory ammo that was not to correct dimensions . at least that's according to some very knowledgeable american forum members that i found out are american gun writers . taken with a grain of salt of coarse..
i use and reload ADI brass in my 308 and 223 "working rifles" . it's very consistent, good quality, and if i lose any out bush it's reasonably priced and replaceable . in my safe pets i use in comps at the range i use good quality brass in rifles like lapua my 222 . i rotate batches , one is on it's 11th firing, tight primer pockets and not a single issue with it . i anneal the necks after every 3rd firing with a "ugly annealer" , which is a great bit of gear . i don't mind paying extra for quality brass that's good a high grade of QC and is made from good quality metal. use what you want , but in some circumstances you get what you pay for .
if anyone in the logan, ipswich, brisabane area with a 7x57 is looking for some factory PPU 7x57 loaded ammo, i have some , it doesn't fit in a standard shell holder, ( it fitted in 6.5x55 shell holder) cause my ruger m77 rifle doesn't like it . you must present a firearms license of coarse. anyone interested PM me . cheers