OOBD’s in AR’s are NOT caused by the floating firing pin becoming stuck forward.
Remember, AR-15 FP protrusion spec is only 28-36thou, and the bolt travel during the locking cycle is over 250thou, meaning when the bolt is unlocked, the firing pin cannot even reach the bolt face by nearly 10x its protrusion…
So OOBD’s are caused predominantly by high set primers, with a much smaller subset occurring by broken FP’s, debris like stacked pierced-primer fragments in the pin bore, etc.
I suppose a broken cam pin could sufficiently bind the FP to cause a slamfire but also allow the bolt into battery sufficiently far to fire, but NOT lock - but again, we typically would expect the case to rupture as the BCG freely moves backwards like a blowback action, and of course, the broken cam pin would be immediately obvious upon inspection of the firearm after this event. Equally, a broken and seized FP could cause an unlocked detonation, slam fire, however, again we’d expect a ruptured case and the broken firing pin would be obvious upon post-event inspection.