They nevertheless do have non-uniform lengths. If you don't trust me, take a batch of brass with exactly the same headstamp and measure their lengths - I have measured hundreds, they do like a truth fluctuate in length. With the FC brass I calculated, Severe spread was around ten 1000's. https://franciscougpaj.blog-kids.com/37965433/indicators-on-9mm-brass-for-sale-you-should-know