Auto Sear Pin M16

Full auto question. Make that a sear block question instead

Complete 7.62×39 Bolt and Carrier Group AR15 – M16 – Maxim Firearms

M16 Auto Sear with Pin-MSAS1

Auto Sear Pin M16

M16 4-Way

M16 Auto Sear with Spring and Pin (RESTRICTED SALES

Hypothetically what would happen if an M16 had an AR15 semi auto

Willfire MFG Division Ambidextrous M16 Drilling Jig - WMD WMD-136

M16 4-Way

Can anyone tell me why this old colt has a 3rd pin but is not a

AR-15/M16/M4 Auto Sear w/Spring and Pin

Auto Sear Pin M16

M16 Full Auto LPK

M-16 Drilling Jig - New Frontier Armory

I dont understand why this is special? : r/ar15