Funnily enough I was reloading some .223 yesterday and trimmed a couple of cases back to just under 44.7mm or 1.76” - they were very marginally over 44.7mm as I use my vernier like a feeler gauge. I use a Lee case trimmer which takes them back to just under 44.7mm.
If I trimmed them shorter, I’m pretty sure they’d just stretch to fill the chamber and thin/crack the necks prematurely?
The rifle shoots far better than me out to 600yrds with factory dimension ammunition, so I’ve never felt the need to experiment with going outside standard parameters!