Second opinion please, am I over pressure?

fwiw I checked the SAMMI specs for a 175gr projo they list the muzzle velocity at 2420fps
133fps slower than your recorded 2573fps
based on that I'd say your at top end for pressure
Yes, but the reason we are having this conversation is that SAMMI says 52,000 PSI or some such is max for a 7x57 so nobody blows up their 1886 Mausers. In a modern firearm with modern brass, 52kpsi is a modest start load at best (270 Win is 65KPSI max, for example).
 
Bi
Cci primers have hard cups. If those were federal, id bet they were flat. Saying that, if say youre fine. No ejector mark. How was bolt lift?
Bolt lift was normal/unremarkable. I could re run the test with Win primers I suppose is a thought...
 
fwiw for 7x57 SAMMI max pressure is 54200psi and 48900cup .... dbyfo
Yes, but the reason we are having this conversation is that SAMMI says 52,000 PSI or some such is max for a 7x57 so nobody blows up their 1886 Mausers. In a modern firearm with modern brass, 52kpsi is a modest start load at best (270 Win is 65KPSI max, for example)
 
So after all the discussion, I think my earlier assessment that 45.5 @ 2525 FPS is probably that 58-59 KPSI I was shooting for, and the hotter stuff is likely getting up and over.
 
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