Two-AZ, You are 100% correct. I just checked and that 1st sectioned round is indeed a AHED 35-mm. I just realized that it is still missing 3 tapering cone shaped sub-projectiles in the windscreen area. Good call!
On a separate note: I tried my first non-saboted sectioning job on this 50 cal. I tried to do it AKMS style by sectioning it directly in half leaving the projectile core intact.