Used 45-70 brass score

[gnappi]

I recently scored a sack of 45-70 brass and this week I started prepping some. I found a number which absolutely would not go unto my sizing die without a copious application of Imperial die wax.

WTH??? No flattened, loose / pierced primers or rim deformations but cases were ~.005" over sized at the base crimp compared to brass that sized normally. 

I'm wondering if some are pushing really old iron to the limits of modern rifles? If so, why?

[bigbore5]

I had an early Handi-rifle with oversize chamber years ago.

[hunter01]

As BB5 said, oversized chamber. Not at all uncommon.